There is a conflict with Jay's birth in 1896 and his mother, Sarah, death death in 1891.I reviewed the Turner cemetery in Rains county and found only a partial listing.Her father-in-law, John Burnell Brown, was there but she wasn't.
I could'nt find Jay's father using the online Heritage Quest census records in 1900.I tried all combinations of John Rufus Brown but to no avail.
You might post at the California state board for the 1930 census for Jay.They seem to be nice out there and answer most posts with the 1930 census.
Maybe some nice person will get you an obituray at the Riverside county board.I searched thru their cemetery listing for Jay but could not find him.
Of course you could go thru the state and shell out some money to get his death certificate. It would only have limited information only as reliable as to the person giving the information.