My mother-in-law stuffed wads of toilet paper in the toilet creating a huge plumbing problem. Now she thinks the toilet is broken because we unhinged the toilet flapper to avoid her flushing and clogging up the toilet. So, she takes the BM out of the toilet and puts it in the trash. We constantly have to watch her now. Help!
Typically, most individuals with autism are "visual thinkers". This is also true of a lot of elders with dementia. In addition, it is common for people with dementia to loose the ability to read - the written word is no longer recognizable or it's lost its meaning or the ability to connect one word to another is lost.
My point? Most children with autism learn best by using pictures. Some can use simple line drawings for pictures and others need actual photos. I know this sounds out there but - try a picture with a poo in the toilet and put a happy face next to it. Put up another picture with a poo in the waste basket and perhaps a red "x" through it and a frowny face. I bet it will work.