Let's play a little word association . I'll start with a statement and someone else follow with a statement that first comes to mind. Chocolate
I thought I did - a blankie is a childs (or parents) term for a blanket, sometimes a particular one that the child is attached to - AKA Linus in Peanuts... Of course, it is used for more than sleeping but as a friend and as a repository for all sorts of incidental goodies - hence your lovely derivation of 'blanket' and 'hankie'...