hi everyone can you help?

[abidjan1]

i was a family member of an EU national and recently been issue a ILR after my 5 years RC . while applying for my ILR i did included my child from from another relationship and the child was issue a 5 years RC as a familly member of a EU national.
Now i am divorcing my EU national and she has left the country.
so i should let the HO know this with regard of the stay in my child passport.
my question now is what application shall i make to the HO for my child residency?

thank for reading