You're both in the same age bracket so that's not an issue. And also i'm with someone who has a little boy who is not mine. You do what you feel is right. Big respect to guys who take on the responsibility of someone else's child. So good luck to you man. Just be sure to treat them equally and as you're own.

I don't see an issue here, no harm in talking to her and just see where it goes.

In that instance it really depends. I can't imagine those kids are very old, so if she brings you into her / their life early on and you guys decide it doesn't work out, now you're tearing the kids apart. 5+ years down the road when you think marriage might be imminent, I'd go ahead and introduce everyone.

A coupe of my friends had this happen, either their dad died early on or wasn't in the picture and their mom was bringing guy after guy home and it destroyed them. One of them committed suicide 3 years ago now, and the other 2 are heavy drug users. I think that the mother / father of the children really need to look at who they're bringing into that child's life and when they do it.