My boyfriend and I are not married, however we've lived together for 2 years and feel as though we are married. The kids (he has twins, I have a son) and our parents treat us like we're married.

I often take care of things such as school stuff, doctors visits, etc regarding the kids with no issues. I've been thinking about it, though and realize I have no legal rights to a lot of things involving them. Is there something we can do (power of attorney?) to ensure that I am allowed to make decisions regarding the twins and vice versa with him and my son?