Hitchhiking spirit
From XFamily - Children of God
David Berg had a recurring interest in the Occult, and demon possession was a belief that fundamentally impacted The Family.
"Hitchhiking spirits" were spirits who would allegedly "hitchhike" on a person or item. It was common for members returning from an excursion outside of the home into the System to pray to cleanse themselves of any "hitchhiking spirits" they might have picked up.
Spirits were often credited for problems with children and teens in The Family and exorcisms, sometimes violent, were common.