When I went back out tonight to check on them one more time (I fed them a few hours ago), the boy had tried to hang himself on the hayrick. The 'rick is too low for him to kill himself, but he was definitely stuck. And, oddly, Zoe had accomplished the same trick in the hayrick on the opposite wall. ::sigh:: The trick is pretty easy - prop the goat's front feet up against the wall, slide its head in where the 'rick rails are wide, and then let the goat slide down inside the gap as the rails get narrower until they close behind the goat's jaws/horns. But, of course, the goats are doing this to themselves.
It is fortunate that Achaosofkittens has lowered most of the hayricks because of the adult goats doing this same hangman move, with almost-disasterous results.