I don't have this specific individual(s) in my Abbott tree but I did do some quick research.
I did find a John Abbott and wife Luilla in the 1900 census records on Ancestry.com for Clermont Co., OH which is just east of Hamilton Co. where you state your John and Luilla spent some of their time (St. Bernard).I don't know if this is the same people or not for the dates of birth differ from what you provided.Here is what is says:
John b. Oct 1867 Ohio.32 years old in 1900 census.Both parents marked as being born in Ohio. Luilla b. Apr 1879 Kentucky. 21 years old in 1900 census. Both parents marked as being born in Kentucky.
He is listed as a Day Laborer and renting the home.
This data was recorded on 5-Jul-1900 Ohio Twsp. Clermont Co., OH Supervisor's District No. 5 Enumeration District No. 40 Sheet No. 11
I could not find him listed in any other census in the area.I did find another John Abbott in KY but I don't think this is the same person for the information on birth and parents was different.He stated he was born in Kentucky and both parents born in England.
I'll keep you in mind if I run accross anything else.