AutoFixture - Likeness. Comparison of complex objects

I am trying to compare 2 complex objects with AutoFixture's OfLikeness but unfortunately without success. While comparing nested objects( also with OfLikeness) works as expected, comparing a master object results with error saying that child objects don't match. I assume that the problem is that Likeness apply semantic comparrer only to a master object and nested objects are compared using default Equal implementation which checks for reference match(May be my assumption is wrong?).

This could clarify what I am trying to achieve:

public Class ComplexMasterObject{
    public ChildFirst child1 {get;set;}
    public ChildSecond child2 {get;set;}
    public string SimpleProp {get;set;}
}

public Class ChildFirst {
    public string SomeStringProp1 {get;set;}
    public int  SomeIntProp1 {get;set;}
}

public Class ChildSecond {
    public string SomeStringProp1 {get;set;}
    public int  SomeIntProp1 {get;set;}
}

Test:

public void TestLikeness_Success()
{
     var expected = new ComplexMasterObject {
         Child1 = new ChildFirst {
             SomeStringProp1 = "ChildFirst SomeStringProp1",
             SomeIntProp1 = 1
         },
         Child2 = new ChildSecond {
             SomeStringProp1 = "ChildSecond SomeStringProp1",
             SomeIntProp1 = 2
         },
         SimpleProp = "ComplexMasterObject SimpleProp"
     };

     var input = new ComplexMasterObject {
         Child1 = new ChildFirst {
             SomeStringProp1 = "ChildFirst SomeStringProp1",
             SomeIntProp1 = 1
         },
         Child2 = new ChildSecond {
             SomeStringProp1 = "ChildSecond SomeStringProp1",
             SomeIntProp1 = 2
         },
         SimpleProp = "ComplexMasterObject SimpleProp"
     };

     var child1Likeness = expected.Child1.AsSource().OfLikeness<ChildFirst>();
     var child2Likeness = expected.Child2.AsSource().OfLikeness<ChildSecond>();

     var masterLikeness = expected.AsSource().OfLikeness<ComplexMasterObject>();
     child1Likeness.ShouldEqual(input.Child1); //Passes
     child2Likeness.ShouldEqual(input.Child2); //Passes

     masterLikeness.ShouldEqual(input); 
     // The provided value `ComplexMasterObject` did not match the expected value `ComplexMasterObject`. The following members did not match:
  - Child1.
  - Child2.
}

When I serialize expected and input objects to JSON and compare the results, they are identical.

I tried to use Resemblance, But it didn't work either:

var proxy = expected.AsSource().OfLikeness<ComplexMasterObject>().CreateProxy();
proxy.Equals(input); // returns false

How can perform a semantic comparison on complex object including nested complex properties?

Thank you in advance.