Jessie could have prevented her traumatic past
When Jessie fell behind the bed, she had plenty of opportunity to crawl out. It's not like Emily was looking at her when she fell; she didn't know she was down there. Also, as time went by, the other Woody's Roundup merch was hidden under the bed. Surely not all of it would have fallen down the back of the bed. It must have been put there, in which case Emily would have spotted Jessie.
Granted, Emily would still have lost interest in Jessie when she reached teenage, but a lot of Jessie's grief could have been prevented.
Correct me if I'm wrong.