diff --git a/1.4/Assemblies/RJW_Menstruation.dll b/1.4/Assemblies/RJW_Menstruation.dll
index f3c80a6..f289122 100644
Binary files a/1.4/Assemblies/RJW_Menstruation.dll and b/1.4/Assemblies/RJW_Menstruation.dll differ
diff --git a/1.4/source/RJW_Menstruation/RJW_Menstruation/Hediff_MultiplePregnancy.cs b/1.4/source/RJW_Menstruation/RJW_Menstruation/Hediff_MultiplePregnancy.cs
index 9ecada1..119613e 100644
--- a/1.4/source/RJW_Menstruation/RJW_Menstruation/Hediff_MultiplePregnancy.cs
+++ b/1.4/source/RJW_Menstruation/RJW_Menstruation/Hediff_MultiplePregnancy.cs
@@ -10,7 +10,7 @@ namespace RJW_Menstruation
 {
     public class Hediff_MultiplePregnancy : Hediff_BasePregnancy
     {
-        protected Dictionary<Pawn, Pawn> enzygoticSiblings;  // Each pawn and who they split from
+        protected Dictionary<Pawn, Pawn> enzygoticSiblings = new Dictionary<Pawn, Pawn>();  // Each pawn and who they split from
 
         public override void DiscoverPregnancy()
         {
@@ -52,7 +52,7 @@ namespace RJW_Menstruation
                 {
                     father = Trytogetfather(ref pawn);
                 }
-                Initialize(pawn, father);
+                Initialize(pawn, father, SelectDnaGivingParent(pawn, father));
             }
 
             foreach (Pawn baby in babies)
@@ -356,7 +356,7 @@ namespace RJW_Menstruation
             Scribe_Collections.Look(ref enzygoticSiblings, "enzygoticSiblings", keyLookMode: LookMode.Reference, valueLookMode: LookMode.Reference);
         }
 
-        protected override void GenerateBabies()
+        protected override void GenerateBabies(DnaGivingParent _)
         {
             AddNewBaby(pawn, father);
         }
@@ -755,12 +755,6 @@ namespace RJW_Menstruation
             pawn.story.traits.allTraits = selectedTraits;
         }
 
-        public override void Initialize(Pawn mother, Pawn dad)
-        {
-            enzygoticSiblings = new Dictionary<Pawn, Pawn>();
-            base.Initialize(mother, dad);
-        }
-
         public string DueDate()
         {
             if (pawn.Tile == -1) return "";
diff --git a/changelogs.txt b/changelogs.txt
index e0b4847..cfa0841 100644
--- a/changelogs.txt
+++ b/changelogs.txt
@@ -1,4 +1,6 @@
 Version 1.0.8.3
+ - Compatibility update for RJW 5.3.0.9
+ - Requires RJW 5.3.0.9
  - Re-added support for Animal Genetics (Continued).
 
 Version 1.0.8.2