diff --git a/src/YuckQi.Domain.Services/YuckQi.Domain.Services.csproj b/src/YuckQi.Domain.Services/YuckQi.Domain.Services.csproj
index 5bc311c..dbe63d3 100644
--- a/src/YuckQi.Domain.Services/YuckQi.Domain.Services.csproj
+++ b/src/YuckQi.Domain.Services/YuckQi.Domain.Services.csproj
@@ -4,7 +4,7 @@
     <TargetFramework>net6.0</TargetFramework>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <Authors>Kevin J Lambert</Authors>
-    <Version>6.4.1</Version>
+    <Version>6.4.2</Version>
     <PackageLicenseFile>LICENSE</PackageLicenseFile>
     <Description>A .NET library for bootstrapping a domain services project.</Description>
     <Nullable>enable</Nullable>
diff --git a/src/YuckQi.Domain.Validation/YuckQi.Domain.Validation.csproj b/src/YuckQi.Domain.Validation/YuckQi.Domain.Validation.csproj
index 8ba0233..5435217 100644
--- a/src/YuckQi.Domain.Validation/YuckQi.Domain.Validation.csproj
+++ b/src/YuckQi.Domain.Validation/YuckQi.Domain.Validation.csproj
@@ -4,7 +4,7 @@
     <TargetFramework>net6.0</TargetFramework>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <Authors>Kevin J Lambert</Authors>
-    <Version>6.4.1</Version>
+    <Version>6.4.2</Version>
     <PackageLicenseFile>LICENSE</PackageLicenseFile>
     <Description>A .NET library providing domain validation fundamentals.</Description>
     <Nullable>enable</Nullable>
diff --git a/src/YuckQi.Domain/Extensions/ObjectExtensions.cs b/src/YuckQi.Domain/Extensions/ObjectExtensions.cs
index 16a63fd..a639a68 100644
--- a/src/YuckQi.Domain/Extensions/ObjectExtensions.cs
+++ b/src/YuckQi.Domain/Extensions/ObjectExtensions.cs
@@ -13,7 +13,13 @@ public static class ObjectExtensions
     public static Dictionary<PropertyInfo, (Object?, Object?)> GetDifferencesByProperty<T>(this T a, T b)
     {
         var properties = GetObjectProperties(typeof(T));
-        var values = properties.Select(t => new KeyValuePair<PropertyInfo, (Object?, Object?)>(t, (t.GetValue(a), t.GetValue(b))));
+        var values = properties.Select(t =>
+        {
+            var valueA = a != null ? t.GetValue(a) : null;
+            var valueB = b != null ? t.GetValue(b) : null;
+
+            return new KeyValuePair<PropertyInfo, (Object?, Object?)>(t, (valueA, valueB));
+        });
         var result = values.Where(t => ! Equals(t.Value.Item1, t.Value.Item2)).ToDictionary(t => t.Key, t => t.Value);
 
         return result;
@@ -22,7 +28,12 @@ public static class ObjectExtensions
     public static HashSet<PropertyInfo> GetNonNullProperties<T>(this T a)
     {
         var properties = GetObjectProperties(typeof(T));
-        var values = properties.Select(t => new KeyValuePair<PropertyInfo, Object?>(t, t.GetValue(a)));
+        var values = properties.Select(t =>
+        {
+            var valueA = a != null ? t.GetValue(a) : null;
+
+            return new KeyValuePair<PropertyInfo, Object?>(t, valueA);
+        });
         var result = values.Where(t => t.Value != null).Select(t => t.Key).ToHashSet();
 
         return result;
diff --git a/src/YuckQi.Domain/YuckQi.Domain.csproj b/src/YuckQi.Domain/YuckQi.Domain.csproj
index cbad02a..9a09d41 100644
--- a/src/YuckQi.Domain/YuckQi.Domain.csproj
+++ b/src/YuckQi.Domain/YuckQi.Domain.csproj
@@ -4,7 +4,7 @@
     <TargetFramework>net6.0</TargetFramework>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <Authors>Kevin J Lambert</Authors>
-    <Version>6.4.1</Version>
+    <Version>6.4.2</Version>
     <PackageLicenseFile>LICENSE</PackageLicenseFile>
     <Description>A .NET library for bootstrapping a domain model project.</Description>
     <Nullable>enable</Nullable>
diff --git a/test/YuckQi.Domain.UnitTests/Extensions/ObjectExtensionTests.cs b/test/YuckQi.Domain.UnitTests/Extensions/ObjectExtensionTests.cs
index 25b0310..17ff7f8 100644
--- a/test/YuckQi.Domain.UnitTests/Extensions/ObjectExtensionTests.cs
+++ b/test/YuckQi.Domain.UnitTests/Extensions/ObjectExtensionTests.cs
@@ -10,6 +10,25 @@ public class ObjectExtensionTests
     [SetUp]
     public void Setup() { }
 
+    [Test]
+    public void Object_WithSomeNonNullProperties_HasExpectedValue()
+    {
+        var a = new { a = new Int32?(), b = 1234, c = "hello", d = new Int64?(9999) };
+        var result = a.GetNonNullProperties();
+
+        Assert.That(result, Has.Exactly(3).Items);
+        Assert.That(result.Select(t => t.Name), Does.Not.Contain("a"));
+    }
+
+    [Test]
+    public void Objects_WhereOneIsNull_HaveAllPropertyDifferences()
+    {
+        var a = new { a = 123, b = "test" };
+        var result = a.GetDifferencesByProperty(default);
+
+        Assert.That(result, Has.Exactly(2).Items);
+    }
+
     [Test]
     public void Objects_WithDifferentStringValues_HaveOneDifference()
     {
@@ -22,14 +41,4 @@ public void Objects_WithDifferentStringValues_HaveOneDifference()
         Assert.That(result.Single().Value.Item1, Is.EqualTo("test"));
         Assert.That(result.Single().Value.Item2, Is.EqualTo("hello"));
     }
-
-    [Test]
-    public void Object_WithSomeNonNullProperties_HasExpectedValue()
-    {
-        var a = new { a = new Int32?(), b = 1234, c = "hello", d = new Int64?(9999) };
-        var result = a.GetNonNullProperties();
-
-        Assert.That(result, Has.Exactly(3).Items);
-        Assert.That(result.Select(t => t.Name), Does.Not.Contain("a"));
-    }
 }