Mrs. Darling first heard of Peter when she was tidying up her children's minds. It is the nightly custom of every good mother after her children are asleep to rummage in their minds and put things straight for next morning, repacking into their proper places the many articles that have wandered during the day. If you could keep awake (but of course you can't) you would see your own mother doing this, and you would find it very interesting to watch her.
This is from Peter Pan. I can't understand the context of "It is the nightly custom of every good mother after her children are asleep to rummage in their minds and put things straight for next morning, repacking into their proper places the many articles that have wandered during the day."
Does "in their minds" mean "in her children's minds" or " in good mothers' minds"? Does "things" and "articles" mean "event" or "something like toys"? A man said "into their proper places" means "in their heads". Right? And which does this "their" mean, her children or good mothers? Could you teach me?