Bellisario has mostly had parts in series produced by his father.
He played Midshipman Michael "Mikey" Roberts in JAG and also appeared during the first part of NCIS season 3 as Charles "Chip" Sterling.
In the pilot chapter of JAG, Michael was the boy rowing in the Adriatic in the aperture scene.
At the end of S03E01, he makes a pizza delivery to a police station.
Michael has two other siblings who are actors: half-sister Troian Bellisario (Spencer Hastings on Pretty Little Liars and Sarah McGee on NCIS) and stepbrother Sean Murray (Timothy McGee on NCIS).