As Madame Alexander starting moving from cloth dolls towards composition dolls, their first efforts in composition were not made by Alexander. It is likely Alexander was buying composition dolls from other companies, and then dressed and marketed them. Some of these very first examples were a little crude, but it did represent a bold new step for the fledgling company. In the mid 1930s, Alexander would graduate into producing their own composition dolls with the 7" all composition Tiny Betty, the 9" all composition Little Betty and the 12" all composition Betty. 1933 there is an Alexander ad for Walt Disney's "Three Little Pigs" — possibly the very first composition dolls made by Alexander.
This 10" all composition baby doll has no markings, and is wearing diapers and a Madame Alexander tagged organdy gown with lace trim. She has painted blue side glancing Goggly eyes, an open mouth for her bottle and, well, a place for it to come out to accomplish the wet feature. While looking for a match, the best example I've found is an ad for a similar drink/wet composition baby doll. My only other clue is the family of the original owner selling this and other dolls. The family knew nothing about the dolls of their aunt who had collected some very good examples of Alexander dolls. If anyone seeing this doll knows more, please do not hesitate to let me know!