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This combination from photos provided by Allentown, Pa., Police Department shows from left, Amy Yu and Kevin Esterly. (Allentown Police Department)
A 45-year-old man who signed a 16-year-old girl out of her Pennsylvania school 10 times before they disappeared was able to do so because she listed him as her stepfather in school documents, officials said Saturday.
Kevin Esterly and Amy Yu were last seen nearly a week ago and "could possibly be endangered," the Allentown Police Department said Wednesday when they issued a missing person alert. Police also issued a warrant for Esterly's arrest alleging interference with the custody of a child.
Authorities have said that Esterly signed Amy out of her charter school 10 times between November 2017 and February without her parents' permission.
The girl's parents contacted authorities on Feb. 9 after they found out he signed her out of school without permission, according to court records.
Esterly was able to do so because the teen had altered her student records to list him as her stepfather, Colonial Regional Police told WFMZ-TV.
MISSING PENNSYLVANIA MAN, TEENAGE GIRL HAVE 'SECRETIVE RELATIONSHIP'
Her younger brother and mother told the television station on Friday Amy met Esterly at church years ago, and Amy is friends with one of Esterly's daughters.
John Yu said after his mother dropped him and Amy off at the bus stop Monday, she took off and he didn't know where she was going.
"She left," John Yu said, "She just walked out, and went somewhere."
Mul Luu, told WFMZ-TV she came home and discovered her daughter's passport missing, along with cash.
When authorities contacted Esterly's wife on Monday, they discovered he had withdrawn $4,000 from her bank account and taken personal documents.
Luu told WFMZ-TV that she discovered text messages between Esterly and Amy on her daughter’s phone, and it sounded like they were in a romantic relationship.
"I pray to God and God help me to bring her back," Luu said.
The Associated Press contributed to this report.