I have only ever once needed to use that form - for a father where a shared custody situation came to exist (since it’s usually filed for the mother in hospital when the children are born). Did you check on RAC to see what/if any kids’ info is on there?
I have a male Canadian client and his non-resident spouse, who are missionaries in Africa. CRA requested a residency determination. They checked all the boxes as missionaries and he gets the CCB, etc for himself and the kids.
I just realized this form does not need to be completed.
It says: Do not fill out this form if you already applied using My Account on the CRA website or when you registered the birth of your newborn with your province or
territory (except Nunavut).