An Allentown woman threatened to send Latin King gang members to kill her father and stepmother, police said.
Megan Koch, 27, also told her parents Sunday night, "One way or another, I'm going to make sure you die," according to Pennsylvania State Police.
Koch's parents, James and Constance, who live outside the Lehigh Valley city, care for Megan's 2-year-old child. After the child spent Saturday night with Megan, the grandparents picked the baby back up on Sunday.
Megan allegedly threatened them for taking her child.
Megan was arrested about 10 p.m. Sunday, and was charged with one count of terroristic threats and two counts of harassment.