Hmmm...I'm not sure about that. Daisy had 2 accidents on my bed this week. Well, the second night was an accident she just had to go so bad and couldn't hold it. I could tell she tried to hold it in. Now, the first night was pure revenge because my husband came home after being away for a few days and he took over "her side" of the bed.
Maybe he doesn't associate your parents bed as "his bed" but he sees your bed as "his" so he doesn't want to go in it.
Maybe he doesn't associate your parents bed as "his bed" but he sees your bed as "his" so he doesn't want to go in it.