Thank you for your response. It's exciting to receive some word from a fellow McKay.
I found where some of your family fits in the whole line. But still can't find a connection to who William's parents are.
Did you have any of the descendents that carried the name Merritt (Merret, Meret)? Several of William's family continued naming one of their children Merritt.
What about your Polly Lanham's parents/siblings? Do you have that tracked?
Thank you again and hope to hear from you soon.