My daughter has 2 kids in 2 years with 2 men. I love them and would like to raise them. How do I ask her to move in?

Ask anything. You can ask anything. It is her choice as an adult to decide what she wants to do with her life, her children, her partners. You can tell her how you feel and what you would like. But you also may need to be prepared to accept her decision, whatever it may be. It can be difficult not being able to make decisions for our children when they grow up, but that *is* what growing up means.