Here is the 1930 US Census for Clark Emery, son of Sarah (Dwire) and David W Emery.
Clark was living in Ottumwa, Center township, Wapello county, Iowa with wife Ella (Clark) their daughter Alice and son-in-law, Harry Whitmore.
The other two children of Sarah and David Emery that were still living in 1930 were Bert and Georgia. I had posted Bert's 1930 Census last year which can be viewed here. I have not been able to locate the census for Georgia.
Benjamin, another son of Sarah and David, may have passed away between 1928 and the time the census was taken in 1930; I've not been able to locate death information or a 1930 Census for him.