This may be an unusual question on here, but I can’t find an answer anywhere. My fiancé passed away on January 2022. We have a one year old and I’m entering my third trimester with our second. Legally how is this gonna work?

Its super important to me that he is on the birth certificate because he is my soulmate and father of both my children even if he is deceased. Its so important to me that BOTH my children have their father’s name on their birth certificate because I always want them knowing who their daddy is and how much he loves them. Is it possible for me to put him on there still?