A rowdy relative was arrested for aggravated assault Tuesday when he threw a 20 pound water bottle at a woman’s head in her Balboa Park-area home, police said.

The victim asked the relative to grab a bottle of purified water from the basement in the 100 block of Judson Avenue around 10:45 a.m. while she was cooking, police said. The ingrate got the water and threw it at the woman’s head, knocking her to the ground.

The woman’s husband called police. When officers arrived they interviewed the suspect who denied the incident, police said. The husband told police it was not the first time this relative had acted out.

The water-bearing bully was promptly arrested, police said.

rnagle@sfexaminer.com