What happens if a student can't get physically through the portrait hole or entrance to their common room?
For instance, there's a portrait "hole" in the Gryffindor common room. What if someone was just a bit too husky to fit inside?
I understand the part about Ravenclaw waiting outside if they can't get in because of a riddle, but what about physical limitations? Do the house elves automatically put you on a diet?
Getting through the portrait hole was simple; as he approached it, Ginny and Dean came through it and Harry was able to slip between them. As he did so, he brushed accidentally against Ginny. "Don't push me, please, Dean," she said, sounding annoyed. "You're always doing that, I can get through perfectly well on my own..."
"Well, it was a bad night for romance all round. Ginny and Dean split up too, Harry."
"Oh, something really silly ... she said he was always trying to help her through the portrait hole, like she couldn't climb in herself."
-Harry Potter and the Half Blood Prince
This would suggest that the portrait hole isn't the large size mentioned (and this is direct book canon). Why would she need to climb out if it was so large, and why would he think that she needed help in the first place?