Simplify the following text for a Grade 10 native English-speaking person.
Original: His name was legally changed to Theodore Sturgeon -- not a pseudonym -- at age eleven after his mother 's divorce and remarriage to William Dicky ( `` Argylle '' ) Sturgeon .
Simplified: His name was legally changed at age eleven after his mother 's divorce and remarriage to William Dicky ( `` Argylle '' ) Sturgeon .