diff --git a/java/src/org/broadinstitute/sting/gatk/walkers/varianteval/evaluators/MendelianViolationEvaluator.java b/java/src/org/broadinstitute/sting/gatk/walkers/varianteval/evaluators/MendelianViolationEvaluator.java
index 6d73310c4..6f2f89fcf 100755
--- a/java/src/org/broadinstitute/sting/gatk/walkers/varianteval/evaluators/MendelianViolationEvaluator.java
+++ b/java/src/org/broadinstitute/sting/gatk/walkers/varianteval/evaluators/MendelianViolationEvaluator.java
@@ -9,6 +9,7 @@ import org.broadinstitute.sting.gatk.refdata.RefMetaDataTracker;
 import org.broadinstitute.sting.gatk.walkers.varianteval.VariantEvalWalker;
 import org.broadinstitute.sting.gatk.walkers.varianteval.tags.Analysis;
 import org.broadinstitute.sting.gatk.walkers.varianteval.tags.DataPoint;
+import org.broadinstitute.sting.utils.MendelianViolation;
 import org.broadinstitute.sting.utils.exceptions.ReviewedStingException;
 
 import java.util.Arrays;
@@ -47,7 +48,6 @@ public class MendelianViolationEvaluator extends VariantEvaluator {
 
     @DataPoint(description = "Number of mendelian variants found")
     long nVariants;
-
     @DataPoint(description = "Number of mendelian violations found")
     long nViolations;
 
@@ -60,47 +60,17 @@ public class MendelianViolationEvaluator extends VariantEvaluator {
     @DataPoint(description = "number of child hom variant calls where the parent was hom ref")
     long KidHomVar_ParentHomRef;
 
-    TrioStructure trio;
-    double mendelianViolationQualThreshold;
+    MendelianViolation mv;
 
-    private static Pattern FAMILY_PATTERN = Pattern.compile("(.*)\\+(.*)=(.*)");
-
-    public static class TrioStructure {
-        public String mom, dad, child;
-    }
-
-    public static TrioStructure parseTrioDescription(String family) {
-        Matcher m = FAMILY_PATTERN.matcher(family);
-        if (m.matches()) {
-            TrioStructure trio = new TrioStructure();
-            //System.out.printf("Found a family pattern: %s%n", parent.FAMILY_STRUCTURE);
-            trio.mom = m.group(1);
-            trio.dad = m.group(2);
-            trio.child = m.group(3);
-            return trio;
-        } else {
-            throw new IllegalArgumentException("Malformatted family structure string: " + family + " required format is mom+dad=child");
-        }
-    }
-
-    // todo: fix
     public void initialize(VariantEvalWalker walker) {
-        trio = parseTrioDescription(walker.getFamilyStructure());
-        mendelianViolationQualThreshold = walker.getMendelianViolationQualThreshold();
+        mv = new MendelianViolation(walker.getFamilyStructure(), walker.getMendelianViolationQualThreshold());
     }
 
-
     public boolean enabled() {
         //return getVEWalker().FAMILY_STRUCTURE != null;
         return true;
     }
 
-    private double getQThreshold() {
-        //return getVEWalker().MENDELIAN_VIOLATION_QUAL_THRESHOLD / 10;  // we aren't 10x scaled in the GATK a la phred
-        return mendelianViolationQualThreshold / 10;  // we aren't 10x scaled in the GATK a la phred
-        //return 0.0;
-    }
-
     public String getName() {
         return "mendelian_violations";
     }
@@ -111,19 +81,14 @@ public class MendelianViolationEvaluator extends VariantEvaluator {
 
     public String update1(VariantContext vc, RefMetaDataTracker tracker, ReferenceContext ref, AlignmentContext context) {
         if (vc.isBiallelic() && vc.hasGenotypes()) { // todo -- currently limited to biallelic loci
-            Genotype momG = vc.getGenotype(trio.mom);
-            Genotype dadG = vc.getGenotype(trio.dad);
-            Genotype childG = vc.getGenotype(trio.child);
-
-            if (includeGenotype(momG) && includeGenotype(dadG) && includeGenotype(childG)) {
+            if (mv.setAlleles(vc)) {
                 nVariants++;
 
-                if (momG == null || dadG == null || childG == null)
-                    throw new IllegalArgumentException(String.format("VariantContext didn't contain genotypes for expected trio members: mom=%s dad=%s child=%s", trio.mom, trio.dad, trio.child));
+                Genotype momG = vc.getGenotype(mv.getSampleMom());
+                Genotype dadG = vc.getGenotype(mv.getSampleDad());
+                Genotype childG = vc.getGenotype(mv.getSampleChild());
 
-                // all genotypes are good, so let's see if child is a violation
-
-                if (isViolation(vc, momG, dadG, childG)) {
+                if (mv.isViolation()) {
                     nViolations++;
 
                     String label;
@@ -151,6 +116,42 @@ public class MendelianViolationEvaluator extends VariantEvaluator {
         return null; // we don't capture any intersting sites
     }
 
+
+/*
+    private double getQThreshold() {
+        //return getVEWalker().MENDELIAN_VIOLATION_QUAL_THRESHOLD / 10;  // we aren't 10x scaled in the GATK a la phred
+        return mendelianViolationQualThreshold / 10;  // we aren't 10x scaled in the GATK a la phred
+        //return 0.0;
+    }
+
+    TrioStructure trio;
+    double mendelianViolationQualThreshold;
+
+    private static Pattern FAMILY_PATTERN = Pattern.compile("(.*)\\+(.*)=(.*)");
+
+    public static class TrioStructure {
+        public String mom, dad, child;
+    }
+
+    public static TrioStructure parseTrioDescription(String family) {
+        Matcher m = FAMILY_PATTERN.matcher(family);
+        if (m.matches()) {
+            TrioStructure trio = new TrioStructure();
+            //System.out.printf("Found a family pattern: %s%n", parent.FAMILY_STRUCTURE);
+            trio.mom = m.group(1);
+            trio.dad = m.group(2);
+            trio.child = m.group(3);
+            return trio;
+        } else {
+            throw new IllegalArgumentException("Malformatted family structure string: " + family + " required format is mom+dad=child");
+        }
+    }
+
+    public void initialize(VariantEvalWalker walker) {
+        trio = parseTrioDescription(walker.getFamilyStructure());
+        mendelianViolationQualThreshold = walker.getMendelianViolationQualThreshold();
+    }
+
     private boolean includeGenotype(Genotype g) {
         return g.getNegLog10PError() > getQThreshold() && g.isCalled();
     }
@@ -181,4 +182,9 @@ public class MendelianViolationEvaluator extends VariantEvaluator {
 
         return true;
     }
+
+
+*/
+
+
 }
diff --git a/java/src/org/broadinstitute/sting/gatk/walkers/variantutils/SelectVariants.java b/java/src/org/broadinstitute/sting/gatk/walkers/variantutils/SelectVariants.java
index 4925a1708..3f6cda8f7 100755
--- a/java/src/org/broadinstitute/sting/gatk/walkers/variantutils/SelectVariants.java
+++ b/java/src/org/broadinstitute/sting/gatk/walkers/variantutils/SelectVariants.java
@@ -70,8 +70,7 @@ public class SelectVariants extends RodWalker<Integer, Integer> {
     @Argument(fullName="discordance", shortName =  "disc", doc="Output variants that were not called from a ROD comparison track. Use -disc ROD_NAME", required=false)
     private String discordanceRodName = "";
 
-    @Deprecated
-    @Argument(fullName="family", shortName="fam", doc="USE YAML FILE INSTEAD (-SM) !!! string formatted as dad+mom=child where these parameters determine which sample names are examined", required=false)
+    @Argument(fullName="family_structure", shortName="family", doc="USE YAML FILE INSTEAD (-SM) !!! string formatted as dad+mom=child where these parameters determine which sample names are examined", required=false)
     private String FAMILY_STRUCTURE = "";
 
     @Argument(fullName="mendelianViolation", shortName="mv", doc="output mendelian violation sites only. Sample metadata information will be taken from YAML file (passed with -SM)", required=false)
@@ -112,8 +111,10 @@ public class SelectVariants extends RodWalker<Integer, Integer> {
 
         if (MENDELIAN_VIOLATIONS)
             mv = new MendelianViolation(getToolkit(), MENDELIAN_VIOLATION_QUAL_THRESHOLD);
-        else if (!FAMILY_STRUCTURE.isEmpty())
+        else if (!FAMILY_STRUCTURE.isEmpty()) {
             mv = new MendelianViolation(FAMILY_STRUCTURE, MENDELIAN_VIOLATION_QUAL_THRESHOLD);
+            MENDELIAN_VIOLATIONS = true;
+        }
 
         // Initialize VCF header
         Set<VCFHeaderLine> headerLines = VCFUtils.smartMergeHeaders(vcfRods.values(), logger);
diff --git a/java/src/org/broadinstitute/sting/oneoffprojects/walkers/MendelianViolationClassifier.java b/java/src/org/broadinstitute/sting/oneoffprojects/walkers/MendelianViolationClassifier.java
index c82be962c..b2ea35249 100644
--- a/java/src/org/broadinstitute/sting/oneoffprojects/walkers/MendelianViolationClassifier.java
+++ b/java/src/org/broadinstitute/sting/oneoffprojects/walkers/MendelianViolationClassifier.java
@@ -18,7 +18,6 @@ import org.broadinstitute.sting.gatk.walkers.LocusWalker;
 import org.broadinstitute.sting.gatk.walkers.genotyper.UnifiedArgumentCollection;
 import org.broadinstitute.sting.gatk.walkers.genotyper.UnifiedGenotyperEngine;
 import org.broadinstitute.sting.gatk.walkers.genotyper.VariantCallContext;
-import org.broadinstitute.sting.gatk.walkers.varianteval.evaluators.MendelianViolationEvaluator;
 import org.broadinstitute.sting.utils.*;
 import org.broadinstitute.sting.utils.collections.Pair;
 import org.broadinstitute.sting.utils.exceptions.ReviewedStingException;
@@ -58,16 +57,18 @@ public class MendelianViolationClassifier extends LocusWalker<MendelianViolation
      *********** PRIVATE CLASSES
      */
 
-    public class ExtendedTrioStructure extends MendelianViolationEvaluator.TrioStructure {
+    public class ExtendedTrioStructure {
+        public String mom, dad, child;
         public HashMap<String,HomozygosityRegion> homozygousRegions;
         public HashMap<String,Integer> homozygousRegionCounts;
         public HashMap<String,MendelianInfoKey> regionKeys;
+        public org.broadinstitute.sting.utils.MendelianViolation mvObject;
 
         public ExtendedTrioStructure(String family) {
-            MendelianViolationEvaluator.TrioStructure struct = MendelianViolationEvaluator.parseTrioDescription(family);
-            this.child = struct.child;
-            this.mom = struct.mom;
-            this.dad = struct.dad;
+            mvObject = new org.broadinstitute.sting.utils.MendelianViolation(family, 0);
+            this.child = mvObject.getSampleChild();
+            this.mom = mvObject.getSampleMom();
+            this.dad = mvObject.getSampleDad();
             homozygousRegions = new HashMap<String,HomozygosityRegion>(3);
             homozygousRegionCounts = new HashMap<String,Integer>(3);
             homozygousRegions.put(child,null);
@@ -414,7 +415,7 @@ public class MendelianViolationClassifier extends LocusWalker<MendelianViolation
     private MendelianViolation assessViolation(VariantContext varContext, RefMetaDataTracker tracker, ReferenceContext reference, AlignmentContext context) {
         MendelianViolation violation;
         if ( varContext != null ) {
-            if ( isComplete(varContext) && MendelianViolationEvaluator.isViolation(varContext,trioStructure) ) {
+            if ( isComplete(varContext) && trioStructure.mvObject.isViolation(varContext) ) {
                 if ( isDeNovo(varContext) ) {
                     violation = assessDeNovo(varContext,tracker,reference,context);
                 } else if ( isOppositeHomozygote(varContext) ) {
diff --git a/java/src/org/broadinstitute/sting/utils/MendelianViolation.java b/java/src/org/broadinstitute/sting/utils/MendelianViolation.java
index 01c076a1c..dab1f51fd 100755
--- a/java/src/org/broadinstitute/sting/utils/MendelianViolation.java
+++ b/java/src/org/broadinstitute/sting/utils/MendelianViolation.java
@@ -17,6 +17,8 @@ import java.util.regex.Pattern;
  */
 public class MendelianViolation {
 
+
+
     String sampleMom;
     String sampleDad;
     String sampleChild;
@@ -29,6 +31,23 @@ public class MendelianViolation {
 
     private static Pattern FAMILY_PATTERN = Pattern.compile("(.*)\\+(.*)=(.*)");
 
+
+    public String getSampleMom() {
+        return sampleMom;
+    }
+
+    public String getSampleDad() {
+        return sampleDad;
+    }
+
+    public String getSampleChild() {
+        return sampleChild;
+    }
+
+    public double getMinGenotypeQuality() {
+        return minGenotypeQuality;
+    }
+
     /**
      *
      * @param sampleMomP - sample name of mom
@@ -97,10 +116,13 @@ public class MendelianViolation {
 
 
     /**
+     * This method prepares the object to evaluate for violation. Typically you won't call it directly, a call to
+     * isViolation(vc) will take care of this. But if you want to know whether your site was a valid comparison site
+     * before evaluating it for mendelian violation, you can call setAlleles and then isViolation().
      * @param vc - the variant context to extract the genotypes and alleles for mom, dad and child.
      * @return false if couldn't find the genotypes or context has empty alleles. True otherwise.
      */
-    private boolean setAlleles (VariantContext vc)
+    public boolean setAlleles (VariantContext vc)
     {
         Genotype gMom = vc.getGenotypes(sampleMom).get(sampleMom);
         Genotype gDad = vc.getGenotypes(sampleDad).get(sampleDad);
@@ -138,7 +160,7 @@ public class MendelianViolation {
     /**
      * @return whether or not there is a mendelian violation at the site.
      */
-    private boolean isViolation() {
+    public boolean isViolation() {
         if (allelesMom.contains(allelesChild.get(0)) && allelesDad.contains(allelesChild.get(1)) ||
             allelesMom.contains(allelesChild.get(1)) && allelesDad.contains(allelesChild.get(0)))
             return false;