A Philadelphia man accused of leaving his daughters in a car parked outside the Parx Casino in Bensalem while he gambled inside is blaming his mother. At a preliminary hearing, 38-year-old Tan Truong’s lawyer said his client thought his mother, their grandmother, was watching the girls, age six and eight.  He has been ordered to stand trial in Bucks County Court on charges of endangering the welfare of children, and prosecutors are considering additional charges against his mother.