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Your Grandfather's name was actually XXXXX XXXXXon Otis. He was born around 1863 in Iowa (the dates varied depending on source). He married Oda Isabel Waggoner in 1898. She was born on July 10, 1883 and died July 25, 1944. James H. died on April 28, 1949 in San Diego.
They moved around a lot and had several children, though I don't know how many survived.
In 1900, they lived in Carbon Wyoming. They had been married 2 years and had no children.
By 1910, they were in Kansas and had Bertha (b. 1902) and Leroy (b. 1903) (later only referred to as Roy) who were both born in Wyoming and James who was born in Kanas.
In 1920, the family was in El Centro, Imperial, California. Children listed are Roy, Maud, Manes, Mary, and Donald.
In 1930, the family was in Silsbee, Imperial, CA. Children listed include Roy E, XXXXX, XXXXX, XXXXX, XXXXX, and Harold.
Also, XXXXX XXXXXon Otis' parents are probably Leroy and Margaret Otis. I found them in the 1870 census.
I am running a search now for images, so if I find them, I will let you know.
Thanks, XXXXX XXXXX hope this helped!