in 1926, he married frances lehman, the daughter of adele lewisohn lehman and arthur lehman of lehman brothers and grand-daughter of adolph lewisohn; they had two sons: john langeloth loeb jr. and arthur lehman loeb; and three daughters: ann loeb bronfman (twin to arthur) who married edgar bronfman, sr.; judith loeb chiara; and deborah loeb brice. he and his wife were collectors of french impressionist paintings including manet, pissaro, degas, cezanne, and renoir. loeb had homes in manhattan, new york, purchase, new york, and lyford cay, nassau, bahamas.