no ! sell the boxster and keep the minivan..
1. there's probably some hot performance and tech chatter on the minivan forums
2. your offspring will find it soo much cooler having a pop that drives a minivan rather than a porsche.
seriously, do we all have to visit and slap you upside the head on this decision ?
the trailer option is a good one. i run two cars as well a range rover with a tow hitch and the boxster, the ranger rover has 4 big comfy seats, fold the seats down and can get an engine block in the back and with a previous RR regularly towed a 38ft sports cruiser with twin diesels. you can literally tow a house with one.
as for how much a passat can tow.. check here
Towing Capacity******** though check with your local regs on max tow weights allowed for the vehicle weight.