My boyfriend admitted he has twin daughters after dating for two years

My boyfriend admitted to me he has twin daughters that he pays child support for. He isn’t in their lives because according to him the mother is crazy and difficult. The mother also waited for the girls to be ten to inform him about it their existence (but he’s known for 6 years). I’ve been dating him for two years and hes failed to mention he had two other daughters.

He has a son and he’s actively in his life and he was upfront about him.I don’t know how to feel I want to have children with him, but the idea of being his third “baby mama” makes me cringe.

I don’t know what to do I’ve tried to bring it up but he gets very defensive and angry. He claims I’m being narrow minded. I’m a 24 year old female and I feel like he has too much baggage. I love him, but how can I let go of these negative feelings?