Hi,

I did more searching and they moved to Idaho.

1910 Twin Falls, Twin Falls, ID
William Hughes, b. Wales, 42, M1-12yrs, farmer
Elizabeth, b. Wales, 46, M2-12yrs
Raymond, b. MT, 18
Ruby, b. MT, 11

1920 Twin Falls, Twin Falls, ID
William Hughes, b. Wales, 51, gold miner
Elizabeth, b. Wakes, 50
Ray Hughes, b. MT, 26, surveyor city
Ruby Hughes, b. MT, 20, stenographer garage

I didn't find death info for William. I don't know for sure if he died in Montana or just where he died.

1930 Long Beach, Los Angeles, CA
Harry Bowyer, b. Canada-English, 24, laundry man @ laundry
Ruby, wife, b. MT, 30, stenographer real estate
Eilzabeth hughes, b. Wales, 68, malaw, widow

1940 Long Beach
Harry Bowyer, b. Canada, 34, truck driver, education-high school 2 yrs
Ruby, wife, b. MT, 40, educ-college 1 yr

I didn't find Elizabeth's death.