The sister of the man accused of killing Etan Patz described in court Friday how their Bible-thumping father would whip them both with belts and forbid them from having sleepovers or birthday parties.

“Everything revolved around the church,” Carmen Foschini, 53, testified.

“If we misbehaved, he would hit us with his belt,” she explained, often calling her brother, Pedro Hernandez, by the name “Peter” at times.

Doing things that didn’t involve the church — such as having friends or hanging out after school — “wasn’t encouraged,” she said.

Foschini also described how her brother was a loner growing up.

“He was very quiet. Kept to himself,” Foschini said.