Surnames for adoption children?

Question

So television has struck an odd question I can't google. Im watching season 2 of Riverdale and without too many spoilers the sisters name a child that was put up for adoption, charles smith. Well this got me to thinking. Is there a system for surname giving to adoption babies? Game of thrones has a system for bastards, but these kids aren't given away usually and do know where they come from, what if it's a doorstep delivery like in meet the Robinsons? Anyone work for an adoption agency?

Answer

The adoptive parents can change the child’s name once they have legal guardianship and full parental rights

Answer

The surname is the surname given at birth regardless. Once legally adopted, the parents can change the child's name legally. I am an adopted child and had my surname changed once adopted

Answer

I did not have a surname before adoption. My “name” was “LDS Social Girl BP” and some number. I was given a legal  full name (first, middle and last) when I was adopted by my parents. My biological mom did not legally name me. 
I just found my biological family, so I actually know what she wanted to name me. I’m very, VERY glad I have the name my parents gave me. It is funny though, she wanted to name me Kendra Brianne or Jessica Anne. I’m actually a Jessica. All my bioM-family knew me as Kendra. When they met me, they called me Kendra. I didn’t have a legal name from her though.

Answer

When your born your legally given a surname so if you go into the foster/adoption system you keep that name. My dad was adopted but kept his birth name. 
If your taking about like babies being left on the step with no name etc then maybe they is a system for what to call them for the min but they will track down the parents and name the child their name as it’s their legal name

Answer

When my Aunt and Uncle adopted my cousin they gave him their surname, they are actually on his birth certificate. They did keep his first name that his biological mother gave him, someone in his family loved him enough to have his name engraved on a baby bracelet that was his only possession so they wanted to honor it. I'm pretty sure for older children the adoptive parent's let them decide if they want their name changed.

Surnames for adoption children?

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