agree with jenny on this
have you ever crated him?
he cant run round then and dogs dont tend to like messing in the bed.
my little pup 15 weeks old we now crate him and have no wee's or poo's during the night, we did start to let him have the run of the room but found puddles that why we crated him and that worked.
also if he has a space of his very own if he feels scared for any reason he can go there, they like it even more if you put a old blanket over the crate but leave the door uncovered.
its like a den then.
even now my older dogs go into the pups crate and they were also crated as pups

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