How do I change ownership of an object

For example, App1 has a Picturebox control. App1 owns the picturebox so it would be correct to say the App1 is both the Parent and the Owner of Picture1.

Now I change Parent's. I make App1's Picture1 a child of App2. However, App1 still owns Picture1. So now you can say that App1 is the owner of Picture1 and App2 is the parent of Picture1

I want to make App2 the new owner. How can I do this