She probably was a celebrity in her day, but that day has gone by.

I think the first name might be Ruthy.

I would agree with derm; it's Kitty Gordon. She was a musical comedy star in the theater back in the olden days, but I guess you've made that assertation youself regarding that last part. I have her pictured on several old pieces of sheet music as being credited with introducing certain songs and based on what I have I'd say she was active in the 1910 to 1925 timeframe. So she was a song and dance lady. 

Actually her clothes are not vintage 1920s but about a decade and a half earlier. And the '24' marker on the photo probably does not represent the year 1924, but is a sequence print number applied by the photographer in New York. Also I didn't read that wiki link derm posted, so let me modify what I said and now say, she was active in the 1900-1920 timeframe. If she continued in the theater after that, she certainly didn't wear clothes like those anymore.

Seeing as that her "K" looks so much like a big gigantic "R" on her signature, I considered that same thing. Actually Ruth Gordon would have been active in the threater in that timeframe as well, playing the part of one of the children in a revival of "Peter Pan" in 1915. Ruth was born in 1896 and would've been 18 or 19 at that time; whereas Kitty, born in 1878 would have been around 40 in 1918.

Kitty Gordon   http://www.imdb.com/name/nm0330373/