Can be easy enough to go off your line when researching. That is why it is vital to check at least some key documents.
Have you looked at John's b. 1893 (your direct line) birth cert? It will show his parents' date and place of marriage.
If as you say, there are two couples with the same name/time frame, you need to be able to verify which are the correct parents for John b. 1893. His birth cert will help you in this respect.
Monica
