antique composition doll knickerbocker?

by SANDRA
(ST.PETE, FL, USA)

I bought this cutie at an 87 year old ladies estate sale. Paid a pretty pennie for her because I thought she is simply adorable.

RACKING MY BRAIN on the internet trying to get info on her. Was told that she was a Knickerbocker doll, but I don't have a clue.

PLEASE is there someone out there that can help me? How old is she, when was she made, who made her? Have attached a picture of her back showing the makers mark hope this helps.. THANK YOU