Did she? Sarah Obama on record as saying in her native language that Barack Obama was a "son of the village." Bishop McRae and others took that as meaning that he was born in the village, but she may only have been speaking metaphorically. Then McRae uses her statement as evidence that Obama was born in Mombasa, on the other side of Kenya.
How much sense does that make? Harry Truman was a proud son of Independence, Missouri. But that doesn't mean he was born there (he was born on a farm elsewhere in the county). And it certainly isn't evidence that he was born in St. Louis.
Sarah isn't actually Barack Obama's grandmother. She's one of his grandfather's other wives. When McRae asked her about Barack Jr. and Barack Sr., about her son and grandson, and then threw in Mombasa there was confusion. I wouldn't say for certain that she didn't know who he was talking about, but I also wouldn't bet the farm that she was trying to say that she was there when Obama was born and the rest of the family was trying to shut her up. It's not the only possibility, maybe not even the most likely.
It's similar with "son of the soil" comments. Mario Cuomo was a "Son of Italy," Jack Kennedy "a proud son of old Ireland," but that doesn't mean that they were born there. Bill Clinton was also a "son of Ireland" and there's a village there that claims him. Nobody bothered that the Clintons were actually his stepfather's family, not his birth father's.
No. Read the affidavits. Granny told the truth that she was at Obamas birth. Her family members “corrected” her when they realised that she had dropped them in it.