Mollie and Charlie?

This is the front and back of the same photo. To me, the boy sitting on the horse on the left looks like the same boy in the previous picture posted that I thought was labeled Moot. I can't tell from this handwriting what the name is but the other names look like Mary E, Marjorie, and John. These would be Grandpa's (William F.) siblings, maybe the name that's unreadable is a nickname for someone? Also, you can see this picture was developed at "The Gurley Studio" in Big Rapids, Michigan.

*Updated
Molly and Charlie must be the names of the horses... the people in the photo (from left to right) are Mary E. Hurst (b. 1913), Martin Hurst (b. 1921-22), Marjorie E. Hurst (b. 1914), and standing is John W. (Bingo) Hurst (b. 1903).