Squiggle, at present your grandson may be depressed with what has been happening in his life. Just keep an eye on him in case this becomes clinical depression - some signs are not sleeping well or sleeping too long, not eating enough or eating too much, cutting oneself off from normal social activities, thinking he's not worth it or that what is happening is some sort of punishment.
Here's to the wonderful world of duvets . I have a summer one, which I am still using, and I have a thicker one for colder weather. I can clip the two together if I really needed to, but I haven't yet needed to resort to that, not even last winter when temperatures outside were exceptionally cold.