Robert married Sara Lee (Thomas) Newburn on 31 May 1929 in Des Moines. It was the second marriage for Sara. Robert lists his occupation as Aviator. I am not sure how long they were married. Robert's father, Samuel K Haynes, worked in the printing industry in Des Moines and Robert lived there during the late 1920s.
Sara (or sometimes seen as Sarah) was born Oct 20, 1905 to Morgan William Thomas and Matilda Ellen (Roberts) Thomas. (Matilda is sometimes seen as Helen or Ellen).
Sarah married Dewight Newbrun (1904-1966) and they had a child Philis (Phyllis?) born around 1925-1927. Not sure when Sarah and Dewight divorced.
Philis Newburn was living with her grandfather and grandmother (Morgan & Helen) in 1940.
I found a very interesting article in the St Louis Post Dispatch from 3 March 1929 in which Robert is mentioned. I'll try this link method again. The article goes into some detail about the local aviation scene.
https://www.newspapers.com/clip/1633...st_louis_1929/
Robert got his training at the Robertson Flying School in St Louis and when he graduated he had a limited commercial license. The article relates a little background on the school and mentions that Robert took his father Samuel K Haynes up for a flight. Samuel K Haynes died in Des Moines of pneumonia in August, 1929. In his obit it mentions he was survived by his wife Ellen Haynes, his son Robert E Haynes and a daughter Mrs A (Alice B) Eastwood of Georgia. No mention of Sara.
And then these from 1932:
https://www.newspapers.com/clip/1633...ynes_st_louis/
https://www.newspapers.com/clip/1633...st_louis_star/