In the 1910 Census Prestonburg Floyd KY is the following: Wallen, Shelby age 28 Wallen, Julia age 25 Wallen, Ethel age 1 (living nearby are Newton Wallen (age 52) and Willie Wallen, possibly father and brother to Shelby)
In the 1920 Census Depot Floyd KY there is the following family: All were born in KY, Shell was a miner.
Wallen, Shell age 41 Wallen, Julia age 40 Wallen, Ethel age 10 Wallen, Charley age 7 Wallen, Claude age 5 Wallen, Becca J. age 2/12
In the 1930 Census, West Prestonburg, Floyd, KY Again, all born in KY, Shell a coal Miner.
Wallen, Shell age 50 Wallen, Julia age 49 Wallen, Charlie age 18 Wallen, Claud age 16 Wallen, Rebecca age 11 Wallen, Mintie age 8 1/12
WWI Draft Registration: Shell Wallen b: 3-12-1880 Middle Creek KY Occupation: Coal Miner, Middle Creek Coal Co. Prestonburg, KY.
Hope this will assist you in your search.Good Luck!