Adding stepdad's last name to bio dad's

[lisars]

What is the name of your state? PA
I'm not sure which board this belongs on but, my daughters ( 12 and 8 ) have asked if it would be possible to add their stepdad's last name on to their bio dad's. There would be no step parent adoption taking place, just adding on his last name to theirs. Can this be done, and how do you go about it? Also, does their father have to agree or since there is no adoption is this something that can be done even if he objects?

 

[nextwife]

Also, does their father have to agree or since there is no adoption is this something that can be done even if he objects?

It can ONLY be done against biodad's objections if the courts agree to issue a court order allowing the name change.