The Mystery of Ethel and Hannah C. (Dedrick) Davis' Daughter

One of the dead-ends in my genealogical research that really irks me is this picture and the persons in it. I know, from the back inscription that this is, "Luena Davis' old home on Front Road in Houghton." Sarah Luena was Ethel and Hannah Davis' daughter. I believe she is pictured astride the horse in the bottom right. To the left, Ethel's children by Phoebe: Samuel A. who married Celia Becker, Lydia Emma who married Frank LESTER, and Warren T.
Back to S. Luena Davis, born 30 Dec 1866. On 12 Nov 1891 in Yarmouth, Elgin, she married William B. Graham. By 1901, they are living in Ridgetown and have a daughter, Anna, born 04 May 1893, according to the 1901 Census of Canada. After 1901, they seem to drop off the face of the Earth.
I've looked for the birth record of Anna N.L. Graham: No such luck. They don't seem to appear in the 1911 Census, despite my suspicion that they may have moved to the United States. It's just a hunch. Anyone care to help me out?

Haven't Posted For Awhile ...

Due to a number of reasons (mostly that I lost access to my gmail account), I haven't really posted for awhile. Sad - I have been extremely busy. Over the next few weeks, I'll fill everyone in on what I have been up to.
One major event occurred last weekend. My maternal grandparents, Lawrence and Grace (Mudford) Dedrick, celebrated their 70th wedding anniversary. They were married in 1941 on a hot August day in Port Burwell, Ontario.
Pictured to the left is a photo taken between 1928 and 1930. It is of the students of Plank Road School in South Walsingham Township, Norfolk County, Ontario, Canada. If anyone is out there, and you recognize someone in the picture, drop me a line at trshelly@shellyfamilytree.com.
By the way, my grandfather is in the second row, 4th from the left. His brother, Wray, is holding the sign. As well, my great Aunts Ruby and Marie Mudford are in it as well as my great Uncles Fred, Harold, and Roy Mudford are in it too. Ruby's then-future husband, Ben "Hokey" Hazen is also in the picture.