I think that the name of your great grandfather is Oliver Edward Downs. He was born in MD on 6 Jul 1877 and he died 1946, burried in Potomac, Montgomery Co,. MD.
Census records for him:
1930 (see lines 37 to 41)
1920 (lines 58 to 60)
1910 (lines 87 to 95)
1900 (lines 41 to 44)
On 1930 your grandfather was 8, they were living in Bethesda and his father (widower) was a gardener, a good reason for your grandfather to work in Country Clubs there.
There are listed with them Edna Dixon (housekeeper), Rebbeca Duley (step daughter) and another son named Paul 5 y/o.
On 1920 your great grandfather (widower) was living in Darnestown, Montgomery Co., MD (he was living in Darnestown in 1910 and 1900 as well). There are two sons with him, Thomas and Morace (his correct name is Maurice as can be seen in the 1910 Census schedule).
At this point, we learn that the mother of Paul and your grandfather should be the second wife of your great grandfather, his first wife was the mother of Thomas and Maurice.
The 1910 Census shows the name of your great grandfather's first wife, Julia. There are listed their children as well, Tommie and Maurice included.
On the 1900 Census are listed the two oldest children of your great grandfather and Julia, Helen L (Helen Lee) and Noah (his correct name according the 1910 Census schedule).
Other supporting records:
- Oliver Edward Downs WW I Draft Reg. Card.
His NEAREST RELATIVE is his daughter Helen Lee Connelly. Helen and her family is living "next door" to him in the 1920 Census schedule, lines 54 to 57.
- Death cert. of his son Noah:
Mother's maiden name listed is Julia Duley. Same last name of the step daughter listed in the 1930 Census record. They must be related somehow.
- Oliver E Downes Find A Grave Record:
The gravestone includes Maurice W 1905-1972 and Edna M. 1912 - .
In the 1910 and 1920 Census schedules is a son named Maurice b. ab. 1904-1908.
Edna Dixon died on 2003, she was recorded as Edna Dixon Downes. She may well be the housekeeper listed in the 1930 Census schedule, and the one who ordered the gravestone after the death of Maurice.
- Edna Dixon Downes Find A Grave Record:
I hope you can get birth/death records that put all the pieces together.