I have two children by the same man and my oldest has her father's last name and the youngest has my last name. He asked me through a mediator if I'd be willing to change the youngest child's last name to his. Stupidly I did agree to it and now I am regretting it. He has not shown he has earned the right to claim her last name as his he wasn't even there to sign the birth certificate!! The man I'm dating now treats my children more like they are his than their own father! He is behind in support and recently reduced his visitation from every weekend to every other weekend. At the time, I thought having both girls' last names the same would omit cofusion but I'm afraid I made things worst because now my current boyfriend cannot adopt her without his consent right? HElP!! :( What can I do? Any suggestions?

1. Whose last name are you wanting to use, the fathers, or yours ?
Sorry could not follow, maybe it was me ?

2. As long as the bio father is involved in the kids life, yes you will have to have his permission to adopt. ( since it takes away all of the bio fathers rights to visitation and all other rights.

Fr _ Chuck, I want to keep mine but I had already ok'd the name change. Do I have the right to change it back to mine? Her older sister has her father's last name because we were together then.
The father and I had separated while I was pregnant with the second child and he denied he was the father the whole nine yards and now he is wanting her to take his name after 2 yrs. The only other question is if it is not possible to change it, can I at least hyphenate it so my name isn't totally lost?

The name change laws in the US, vary by state, each state has their own laws. So with that, it is hard to say, the official answer is of course check with an attorney, but since a name change is so simple, you fill out a form at the county clerk, and file it, You may be able to just go down to the court house and ask.