Welcome back to the Wefugees Community and thank you for reaching out to us again.
It is very good to hear that you will qualify for the permanent residence permit (Niederlassungserlaubnis) soon. This is a big step. The minimum age for children obtaining a "Niederlassungserlaubnis" is 16 years. The residence of children under 16 is dependent on the parents' legal status as explained in section 34 of the German Residence Act:
Children’s right of residence
(1) In derogation from section 5 (1) no. 1 and section 29 (1) no. 2, the temporary residence permit granted to a child is to be extended as long as a parent possessing the right of care and custody holds a temporary residence permit, permanent settlement permit or EU long-term residence permit and the child lives together with the said parent as part of a family unit, or if the child would have a right of return pursuant to section 37 if he or she left the federal territory.
(2) When a child comes of age, the temporary residence permit granted to the child becomes an independent right of residence which is unrelated to the purpose of the subsequent immigration of dependants. The same applies to the granting of a permanent settlement permit and an EU long-term residence permit or if the temporary residence permit is extended accordingly under section 37.
(3) The temporary residence permit may be extended as long as the conditions for granting the permanent settlement permit and the EU long-term residence permit have not yet been met.
I hope this helps and please don't hesitate to get back to us with any further questions.
All the best for 2022,