step-grandmother, 繼祖母

FILE – In this Thursday, Feb. 5, 2008 file photo, Sarah Obama, step-grandmother of President Barack Obama, sits in the living room of her house in the village of Kogelo, near the shores of Lake Victoria, in Kenya. On Friday, July 24, 2015 Obama is due to arrive in Kenya, the country of his father’s birth, for the first time since he was a U.S. senator in 2006, and the first stop on his two-nation African tour in which he will also visit Ethiopia. (AP Photo/Ben Curtis, File)
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Karibu: A homecoming for President Obama in Kenya
http://darkroom.baltimoresun.com/2015/07/karibu-a-homecoming-for-president-obama-in-kenya/#1
歐巴馬訪肯亞 繼祖母將為愛孫下廚做飯 - Yahoo奇摩新聞
莎拉•歐巴馬（Sarah Obama）
莎拉是歐巴馬祖父胡笙．歐巴馬（HusseinOnyango Obama）的第3任妻子
並非歐巴馬血親
https://tw.news.yahoo.com/%E6%AD%90%E5%B7%B4%E9%A6%AC%E8%A8%AA%E8%82%AF%E4%BA%9E-%E7%B9%BC%E7%A5%96%E6%AF%8D%E5%B0%87%E7%82%BA%E6%84%9B%E5%AD%AB%E4%B8%8B%E5%BB%9A%E5%81%9A%E9%A3%AF-190503944.html