Super easy and cheap fix to make potty seat fit
elongated toilet seats! Materials needed: 1/2" pvc pipe 7.5" long total length, silicon tape that sticks to itself (fixes leaks in plumbing pipes - Rescue Tape is a brand name but any will work) and one child's toilet seat with hook slot at rear of seat.
Cut 45 degree ends on each end of the pvc - or measure your toilet seat from underneath. Put rubber tape on ends of pipe, tape pipe to toilet seat using the "hook" hole underneath - rotating pipe so that it "grabs" the toilet seat as shown on photo #2. You can use a little longer pipe if you want - this just ended up being 7.5 inches for me - but you want to force the seat to be at the very front of the adult toilet seat.... Hope it works for others!