A.C.
Hi C.! I took the slow road to potty training..so I don't know how well it would work given your grandson's age, but at 16 months I put the potty in the bathroom. My daughter took to it right away..here and there. I just left it as "casually there". As a reward for using it I would give her a sticker(s). Over time, she just sort of naturally took to it more and more. I used a no pressure system..and it worked very well. At 2 and 2 months she was totally trained, except for nap and bedtimes. Being that your grandson is strong minded, this approach might work for him too...make it seem like there is no pressure, and his idea. Good luck!!!