No, sorry - I didn't keep the link, although it would not be hard to find. I did listen to the audio which was of poor quality and the translation of what the woman said was rather doubtful, she appeared to be referring to the birth of the son of a kenyan goat-herder, NOT the birth of zero.
That she might have been present at the birth of the son of Onyango Obama and one of his wives, Akumu, makes perfect sense to me. He was born in the village in 1936 iirc, so Sarah would certainly have been there.
She did say this in an interview with The Daily Nation:
This is a show of blessing from God, since I have always dedicated my time to tend to the orphans. Even the US president passed through my hands added the grandmother."