I don’t know about my own as a kid, but we kept our two children’s potty chair until they were seven and nine. We only had one bathroom in our first house and kept the potty in the laundry room for emergencies. If you used it you had to leave a note on the sideboard so we could empty it. Most times it was for peepee but if the kids were having a bit of the runs then they did poo in it a few times. In addition, several of their cousins who were sleeping over used it also. We always had a small package of wet wipes near it and a coffee filter inside it ready for easy cleanups. I think it’s hard to imagine a nine year old kid using a toddlers potty, but quickies can even make the most holdout kid willing to break down and bite the bullet.