Kentucky

I am not even sure where to start with this. I have searched and searched for answers but no one seems to be able to help me. In 2009 I gave birth to my daughter. I wasn’t married to her father at the time of me having her so he isn’t on her birth certificate. In 2010 we got married & in 2011 we had a baby boy. When he was 8 wks old he suffered from a very traumatic brain injury at the hands of said father. From the day after this happened he hasn’t laid eyes on my daughter and has been in prison since 2012.. in 2016 at five years old my little boy passed away because of complications from the abuse he received. Even on his death certificate it is ruled a homicide and we are currently going though court again because his sentencing is changing. I have been re married now for almost 3 years and I have been with my husband since my daughter was almost 4 and son was 16 months (she was two when her bio dad shook her baby brother). My husband now is wanting to adopt her as we have two more children together. I know this is all a lot to take but I am just looking for someone who could put me in the right direction. I was going to start with having her name changed because she absolutely hates having the same last name as the man who ultimately killed her baby brother. I still am supposed to notify him though but I don’t even know how to do that seeing as I don’t have any contact with him.