Hyphenated Last Name

Me and the father of my child are not together, we dated in the past and things just didn’t work out. I am suggesting that we hyphenate baby’s last name (mine-his)

I have a two year old who carries my last name because his sperm donor decided not to be a part of his life but I want him and his sibling to share a last name regardless of not sharing fathers.

Second I feel like being that I doubt I’ll wind up marrying my second child’s father I feel like a hyphenated last name is a even trade it will allow all of my kids to have the same last name and still allow him to carry on his “name sake”