It also depends where in the Philly Area OP lives. The Amtrak Station is Dowtown- OP needs to consider cost/convenience of driving there or taking an Uber or a regional train into Philly.

If OP is unfamiliar with Amtrak, there are other Amtrak stations which may be closer and less crazy than 30th Street. Amtrak stops in Wilmington, DE (I think every NEC train stops there-if not the great majority do. It's my home station- busy for its size, but very manageable) and in Trenton NJ. Again, you'll have to make sure the train also stops at Newark)

One other issue is the age of the kids, which determines how much assistance they need with transfers, etc