Looking for Mr Donavan

Looking for Mr. Donavan who married Ophelia Walters, not sure of the year. She is the daughter of Jerden J. Walters and Mary Jane Grogan Walters. She died in 1950 and is buried in St. Helena Public Cemetery in St. Helena, Napa Valley, CA. Her siblings are: Alice Walters Overhulser, Marcellus "Blackjack" Walters, John Lee Walters (my great grandfather) and Jerden J. Walters, Jr. Any help would be appreciated.