Creating objects that inherits 2 other objects individual information?

I'm looking to make a Java program which can take information from 2 objects and generate a third while considering the 2 previous objects' individual information. Let's say object "Dog 1" has a white pelt and "Dog 2" has a black pelt. The generated "Dog 3" could then get a pelt ranging anywhere from white to black.

My question is: what do I need to focus on/learn in Java to be able to create this type of Roller/generator?