She's his Niece.
Catch up fools.
"U.S President Barack Obama snuggles with his niece Savita Ng after his sister, Maya Soetoro-Ng, and her family dropped by the Oval Office of the White House December 4, 2015 in Washington, DC."
https://www.alamy.com/stock-photo-us-president-barack-obama-snuggles-with-his-niece-savita-ng-after-93364174.html?pv=1&stamp=2&imageid=199061F5-2C05-4E4F-9F2D-6D2658B36F24&p=142401&n=0&orientation=0&pn=1&searchtype=0&IsFromSearch=1&srch=foo%3dbar%26st%3d0%26pn%3d1%26ps%3d100%26sortby%3d2%26resultview%3dsortbyPopular%26npgs%3d0%26qt%3dmaya%2520soetoro%2520ng%26qt_raw%3dmaya%2520soetoro%2520ng%26lic%3d3%26mr%3d0%26pr%3d0%26ot%3d0%26creative%3d%26ag%3d0%26hc%3d0%26pc%3d%26blackwhite%3d%26cutout%3d%26tbar%3d1%26et%3d0x000000000000000000000%26vp%3d0%26loc%3d0%26imgt%3d0%26dtfr%3d%26dtto%3d%26size%3d0xFF%26archive%3d1%26groupid%3d%26pseudoid%3d%26a%3d%26cdid%3d%26cdsrt%3d%26name%3d%26qn%3d%26apalib%3d%26apalic%3d%26lightbox%3d%26gname%3d%26gtype%3d%26xstx%3d0%26simid%3d%26saveQry%3d%26editorial%3d1%26nu%3d%26t%3d%26edoptin%3d%26customgeoip%3d%26cap%3d1%26cbstore%3d1%26vd%3d0%26lb%3d%26fi%3d2%26edrf%3d%26ispremium%3d1%26flip%3d0%26pl%3d