There are certain circumstances in which kids need permanent residency permits, too.
Newborns in Sweden
If you are an EU citizen and you fulfill the requirements of right of residency, you do not need to apply for a permanent residency permit for your newborn.
If you have had to apply for a permanent residency permit for you, your newborn will need a permanent residency permit, too.
Moving kids to Sweden
If you are an EU citizen and your kids hold EU passports they have automatic right to live and reside in another EU country e.g. Sweden.
If you are a non-EU citizen and your kids hold a non-EU passport, you will have to apply for a permanent residency permit for your children, too.
If you are moving kids to Sweden and one or both of their parent’s already lives in Sweden with a right to permanent residency, you will have to apply for permanent residency permit.