[1] He was a co-founder of the locally renowned Indianapolis architectural firm of Vonnegut and Bohn, and was active in a range of residential, religious, institutional, civic, and commercial commissions.

[2][3] Growing up in Indianapolis, he was described as the opposite of his father: artistic, extremely modest, retiring, unsociable, slightly introverted.

Family lore relates that he had wanted to work as a theatrical designer after becoming stagestruck, "but learned that almost no one could make a living at that--so he became an architect instead.

The "Schnull-Vonnegut clan was slightly condescending," and considered near the top of "the pecking order in the social hierarchy of the community, and particularly in the German group...."[5] The couple had three children: Kurt (1884–1957), Alex (b.

He frequently suffered indigestion and headaches and died at the age of fifty-three, only two years after his father, of intestinal cancer, never living to see any of his children married.

The firm went on to create many landmarks in Indianapolis and greater Indiana, and a number have been listed on the National Register of Historic Places.

[6] In 1888, Julia Schnull, the sister of Vonnegut's mother, married J. George Mueller, the secretary-treasurer of the Mooney-Mueller Drug Company in Indianapolis.