William and Lillias (Kenney) Tremaine

I've been going nuts trying to find William Sremain, who married Lillias Kenney (Hearne History page 187). The name didn't show up anywhere in any census. A little luck and the the unusual name of the son, Breckinridge, led me to them living in New York in 1920. Sremain is a typo; the real name of the family is Tremaine. There are other identifying aspects of this family. William was stationed at Fort Ethan Allen near Burlington Vermont. The census shows that Richard was born in Vermont.

Family 558, West 143rd Street.
William Tremaine, head, M, W, 54, Md, Wisconsin, New York, Wisconsin;
Lillias Tremaine, wife, F, W, 34, Md, Delaware, Delaware, Delaware;
Breckinridge Tremaine, son, M, W, 14, sgl, Delaware, Wisconsin, Delaware;
Richard R. Tremaine, son, M, W, 11, sgl, Vermont, Wisconsin, Delaware;
Lavinia Johnson, servant F, W, 24, sgl, Delaware, Delaware, Delaware;
Census 1920, New York, New York, Manhattan, Assembly District 21, District 1428, pg 45.

Ha! If I'd paid attention I would have noticed that Hearne corrected the name in the 1912 Addendum to his book on page 766. I guess it shows my logic was correct. "Page 187. On March 3, 1908, Richard Rolland Kenney, married Miss Marionetta Walker, who was a girl friend of his first wife, and of same age, also Sremain, should be Tremain."

I also found Breckinridge and Richard in the 1930 census, but they are living with their grandparents, Senator Richard Rolland Kenney and Marianita (Walker) Kenney. Wow! Look at the size of that stately house. Twice as big as the next biggest house on the block!

Family 91, 11 North State
Richard R. Kenney, head, house $30000, M, W, 72, Md 24, Delaware, Delaware, Delaware, employment none, veteran WW(I)
Margeta W. Kenny, wife, F, W, 70, Md 12, Delaware, Delaware, Delaware;
Richard Tremaine, grandson, M, W, 27, sgl, Delaware, Wisconsin, Delaware, utility man, oil;
Breckenridge Tremaine, grandson, M, W, 24, sgl, Vermont, Wisconsin, Delaware, utility man, powder;
Census 1930 Delaware Kent Dover City Ward 3 Pg 59

William and Lillias seem absent in the 1930 census. Why? Perhaps both of them died between 1920 and 1930, or perhaps the children lived with grandparents during the depression.