Brother David
The deceased David Obama is a brother of Mark Ndesandjo. Both Mark and David are the sons of Ruth and Obama Sr., and half-brothers of Obama. When she remarried the boys took their step-father’s name but when David became a teen he rebelled against his mother’s American ways and renamed himself David Obama.
He eventually ran away from home and was found wandering the streets of Nairobi by Roy aka Abongo Malik. Roy took him in and one night the two went out on Roy’s motorcycle, ending up in a bar. Roy got into a fight at the bar and was arrested. He gave David the keys to his motorcycle before he was taken to jail. David, having been drinking as well, got into a crash on Roy’s motorcycle and died as a result.
There have been bad feelings between Ruth’s and Kezia’s families ever since. By all indications David was born in 1968-1969 and died in 1986-1987 before Barack visited Kenya.
You say...The boy on the left is the child Mark identified as 'David'
There's a point there...kind of like Eddie Munster.