Sean Stewart, Rod Stewarts’ son, was involved in an altercation at a Hollywood party on Saturday night and now he’s under investigation for assault with a deadly weapon.

He and two other male friends went to a private Hollywood home on Saturday night and tried to attend the party that was in full swing. When they were told that they weren’t welcome. Stewart got upset. Apparently people leaving the party were teasing him.

At about 4 a.m. Stewart and his friends started throwing rocks, bricks a mailbox, and a trash can at a ford F150. A husband and wife were inside the truck at the time Stewart and his two friends got the truck door open and started punching the man and woman.

The woman sustained injuries to her legs – lacerations from the windshield glass, and was taken to Cedars Sinai Hospital after the attack for treatment.

Hollywood detectives are investigating the incident.