Nanny Needed - Full-time / Part-time

My 13-year-old nephew has an intellectual disability called Cabezas syndrome which includes developmental delay (he is at a 5-year-old age level), speech impairment, and hyperactivity. Someone will be there with the sitter (mom or grandma) so we are looking for someone to come and assist with watching him during the day. It would mainly be playing with him and helping with calming him down when he gets too hyper. He is a very sweet boy and such a hoot to be around but now that he is older, having an extra set of hands would be helpful.