Hi, welcome to JustAnswer!. This is Ed.
If your daughter's van doesn't have a CHECK ENGINE lamp illumination after the no-start events, chances are very good that the problem is with the vehicle's anti-theft system. Loss of communication between the BCM and PCM will inspire the PCM to shut fuel down after engine start when an OK-to-run message isn't received... triggering the anti-theft response.
The most common source for the sort of loss-of-communication error that your van would have is with a single solder joint that is held in the printed circuit board of the instrument cluster's printed circuit board.
More that just a printed circuit board, it's an entire processor that has a great many duties for the vehicle, including support of the very bus network that is its very employer. If something happens to the 2.5v bias that supports the CCD bus, everything comes to a screeching halt.
One particular solder joint on the cluster's circuit board tends to fracture with time and use, causing circuit voltages to rise in the cluster, affecting the CCD bus. Remember that if voltages rise much above 2.5 volts, the entire network pretty much crashes.
By slapping the dash above the cluster when the van is acting up, you may rattle the electrical connection enough in the cluster to form a positive diagnosis. A return to normal from such an event is enough for me to conclude a problem exists right about where my palm hit.
Replacement of the board can be done at the dealer for about $650 (board) and $300 (labor). A new circuit board must be calibrated by the dealer before the tach or speedo will become operative, or you could just replace the thing yourself.
A simpler solution would be to pull your cluster and fix the solder joint yourself if you're the adventurous sort. It's not that difficult and aside from investing in a fine-tip soldering iron, there would be almost no cost. Let me know and I'll be happy to send you a step-by-step test tutorial to guide you through the process and this is included with a favorable rating.