Did John Hancock have any siblings from John and Mary Hancock?

no he didnt

He had two siblings, Mary and Ebenzer (aka Eben)

, John Hancock had 2 siblings named Mary (named after her mother; oldest) and Ebenzer (youngest). John was the middle child

Yes, John Hancock had 2 siblings named Mary (named after her mother; oldest) and Ebenzer (youngest). John was the middle child

another Hancock