Adoption birth certificate

[baby2xx]

My partner has been my sons 'step dad' since before he turned one, he's now 5. Birth father or sperm donor as we like to call him has never been in my son's life and isn't on his birth certificate. Myself and my partner get married soon as we are really keen for him to officially adopt my son. I have heard that when a step parent adopts in the UK then the birth mother becomes 'adoptive mother' on the birth certificate. Does anyone know if this is true? I think is madness if it is, it will be hard enough telling my son one day that his dad actually adopted him but it will also look like I have adopted him too...

You will both adopt him as far as I understand it and he will no longer have a birth certificate but an adoption certificate.
Does his step dad have to adopt him? You could change his name by deed to have dad's surname and look at what is needed to make him legal guardian.
Maybe ensure your will states dad is to bring him up in the event of anything happening to you.
Or just do the adoption to make him legally your partner's and explain it to him when he is old enough.

This used to be the case, but not any longer. The birth mother doesn't adopt her own child now. When you are ready to start the process you need to contact the adoption team at your local council. Even though the birth father is not on the birth certificate the Court will want him contacted if possible and searches will be made to establish his whereabouts and he will be asked his views on the proposed adoption.

You can’t adopt a child you are already legally the parent of.

Cerificates of adoption (in England at least) don’t mention mother or father, they just name the legal parents. Surely as he is five he already knows and understands that your partner isn’t his birth dad.