Have you looked for John Morrison in the 1940 by using the nickname of "Jack" or his middle name of Patrick?
Here is that same household group in the 1920. I had a hard time finding them so did it by a 1st name search.
1920 US Federal Census
Brooklyn Assembly District 22, Kings County, New York
648 Hendrix Street
-William Nachunson, Head, 45; Immigration year: 1883; Naturalized 1904; b. Roumania - Deaf & Dumb crossed out & replaced with Yid.,
Parents b. Roumania - Yiddish; Occupation: Machinist - Ship Yard
-Julia Nachunson, Wife, age 42; Immigration year: 1883; b. Roumania - Deaf & Dumb crossed out & replaced with Yid.,
Parents b. Roumania - Yiddish
-Ruth Nachunson, Daughter, age 17, b. NY
-Jack Nachunson, Son, age 12, b. NY (c. 1908)
-Bernard Nachunson, Son, age 6, b. NY