A 20-year-old Pennsylvania woman remained in jail yesterday on an assault charge in the stabbing of her stepfather at his home, apparently because the stepfather had argued with her boyfriend, Westminster police said.

Robyn Lee Garrison of Hanover was charged Tuesday night with first-degree assault in the stabbing of Charles Joseph Hamilton, 42, of the 700 block of Young Way in Westminster, police said.

Hamilton, who refused medical treatment, had a small puncture wound in his stomach and a cut over his eye from a kitchen knife that broke after the first blow, police said.

Garrison went to the home after hearing of an altercation between her stepfather and her boyfriend, 24-year-old Steven Sykes of Westminster, police said.

She surrendered about 11 p.m. Tuesday, about five hours after the incident was reported, and remained at the Carroll County Detention Center yesterday in lieu of $25,000 bail.