I think there were suspicions but no facts until the Feb 9 date that the mom discovered her was removing her from school. Then that seems to be a showdown and he was ordered by PD to stay away.
The mom seems to have a different though similar name to the daughter so I'm thinking there is some sort of non-traditional/ family no father siutation at home and maybe some teen problems.
According to one of the commenters on the Allentown page they met at a Baptist church,. So he was scoping around the church and again found a teen with some troubled IMO. He somehow gains the trust of the family to help with the teen to compensate for the gaps in homelife,and she sees him as a strong figure to fill in the gaps. Seems like he stole a page out of Tas Cummins playbook.