Rules to become German for Children and Spouses of foreigners who become German

How do children to foreigners with foreigners, foreign partners to another foreigner, gain German citizenship. What are the rules?

Kids:

• If a child is born to a foreigner who has been in Germany legally for 6-8yrs and/or has had a permanent residence permit (unbefristete Aufenthaltstitel) for at least 3yrs even without taking up German citizenship, the child can take up German citizenship in addition to the citizenship of the parents country of origin and have dual citizenship until the child turns 18 when they choose which citizenship to keep. The child has to choose latest by the 23rd birthday. The freedom of choice is named the Optionszwang (Read the article on: Optionszwang and dual citizenship in Germany )
• If a child’s parent(s) take(s) up German citizenship when the child is still below 18yrs, then the child automatically has a right to get German citizenship as well.

UPDATE: The Optionszwang law was abolished and Germany finally allowed dual citizenship for children who take up German citizenship at birth in addition to that of their parent’s country of origin, this however comes with a caveat. (Read: Germany Allows Dual Citizenship for Kids BUT With a Caveat)

Partners:

• If you spouse takes up German citizenship then you become legible to take it up as well.
• Although these are stipulated by law, some ABs might try to make life quite difficult by asking for wierd documents to make this impossible.