Our daughter is 2 years old, and she is in a registered Montesorri pre-school at the moment.
Citizenship by Descent should be no problem for you, just make sure you have all the right documents before sending them to the officials in Windhoek, otherwise it will delay things.
We are still waiting for our daughter's answer on this question, and we applied in October 2013....
I am a UK national by birth, and I have domicile and just recieved my Certifcate of Identity, (Spetember 15th 2014) nearly a year after I applied. The Certificate was signed and approved in March 2014, but they didn't send it to me until September. I chased them every week since December for this document to finally get it 6 months after it was signed.
The lesson here is to chase things thoroughly and not give up....
Mike