Simplify the following text for a Grade 7 native English-speaking person.
Original: Shaka Sankofa ( born Gary Lee Graham ) ( September 5 , 1963 -- June 22 , 2000 ) was a Texas death-row inmate who was sentenced to death at the age of 18 for the murder of fifty-three year-old husband and father Bobby Grant Lambert in Houston , Texas on May 13 , 1981 .
Simplified: Shaka Sankofa aka Gary Graham born Gary Lee Graham ( September 5 , 1963 - June 22 , 2000 ) . Sankofa was put to death for the murder of fifty-three year-old Bobby Lambert in Houston , Texas on May 13 , 1981 .