My FIL weighs about 90 pounds and is dying, now on hospice. He wears pull-up diapers at night, but often has what can only be called a "diarrhea explosion." The hospice nurse said he was wearing the correct kind, but he's so thin, the diapers leak from the legs.
Any suggestions?
Using disposable chucks layered under him and maybe one over him at night can help keep it contained.
I would give him probiotics to see if you can't stop the diarrhea, maybe some fiber gummies to bulk it up, as well, which should help firm things up.
I hope you find something, this is a tough situation.