My Snuggle Ducky

When I was three I was put to bed in what was called a "Snuggle Ducky". I was zipped up, laying on my back, my arms over my head unmovable. The "Snuggle Ducky" was tied to my crib. I don't remember feeling trapped. I must have felt secure. But now I can't stand to sleep in a bed with sheets tucked in at the bottom or sides. I also have a history of feeling trapped. No wonder!