You and your friend need to change the timing belts yesterday. Most newer Toyotas that had timing belts are not interference engines. Nissan has pretty much eliminated timing belts, and their chains are designed to last the life of the engine. Of course if you hear one rattling like crazy it might be worth replacing if the oil in that engine is not running out the tailpipe.
Timing Belts: Is Your Engine an Interference Engine?
regards
Mech