Baby Doll 1930s - 1960s? unknown manufacturer

Hello!  This doll has been in my family since I was a child.  My mother can't remember if it was hers in the 1930s - 1940s or of a later vintage and given (maybe as a hand-me-down) to my sister in the 1960s.  She doesn't remember any particular clothing or accessories coming with it.  It is all hard plastic, at least I assume its plastic. The button in the belly area supposedly connected to an internal mechanism that  moved the position of the head, but hasn't worked as long as I remember. I am fond of it but don't collect dolls so I don't know much about it and don't want to just dump it in a donation bin or turn it back into a plaything for young children if it would be of value to someone. Thanks for any information you can give, even hints!