A few pieces for a timeline:
18 Apr 1910 - Waller County Census. Mollie (22) was living at home with her parents, William and Cassie Cameron. She (and her sister Artie - later known as "Tot") was a public school teacher.
27 Apr 1910 - Grimes County Census. F.A. Hamer was living in the household of Sam and Rebecca Levy, along with several other boarders. Frank was the City Marshall of Navasota.
1913 - Houston City Directory. Francis A Hamer was living at 810 Walker Ave, Houston.
1919 - Houston City Directory. Mrs. Mollie Hamer had rooms at 2 Rose Apartments, Houston. She was a stenographer.
8 Jan 1920 - Harris County Census. Mollie Hamer was living at 322 Bayland Ave, Houston, with her sister "Tot", Paul Nagel and their 1 1/2 year old daughter Glenn. Mollie was a stenographer for a bank. Paul was a commercial traveller for a wholesale grocery company. Mollie was 'widowed'.
1923 - Houston City Directory. Mrs. Mollie Hamer was living at 523 Bayland Ave, Houston. She was a stenographer. (This is probably again with Paul and Tot - in 1925, they were at this address, and in later years lived at at least one more address on Bayland Avenue).
1925 - Houston City Directory. Mrs. Mollie C. Hamer was living at 1404 Jefferson Ave, Houston. She was a stenographer.
12 Apr 1930 - Harris County Census. Raymond E. and Mollie C. Ford were living at 1306 Waugh Drive, Houston. The address had four families, as did several others in the immediate area. Raymond (as well as his parents) had been born about 1896 (ie, about 8 years younger than Mollie) in Kentucky - he was employed as a salesman for Who-Wire-Rope. Mollie was a secretary for an oil company.
22 Aug 1937 - Death Certificate. Mollie was living at 628 Sul Ross, Houston. The informant for the certificate was J.H. Cameron, of Hempstead (Not certain who this was. In 1930, there is a John H. and Irene Cameron living in Hempstead, but not sure of any relationship...). I am not able to make out the location in Precinct 6 of Waller County where the "accidental drowning" occurred.