In the UK the parents have to legally adopt the baby as it was born to another woman despite whatever genetics, afaik.
Did we ever see Archie’s birth certificate?
my thinking is that there are children - it would be impossible to keep everyone around them silent
or silenced! without the smallest ripple turning into a full blown tsunami. It would be the biggest news ever. Also they have to keep up the pretend children forever; school, college, marriage etc. it’s enough of a stress to kill you off or the humiliation of pretending you have children would kill you.
I do think they were born by surrogate though.