Just got your message and you were asking if my John McAlonan might be a brother of Robert. I know they were born a couple of years from each other. Is Robert's father named Thomas McAlonan, as that is what John's father is called. John McAlonan is my 3rd Great Grandfather and Thomas McAlonan is my 4th Great Grandfather. Thomas was married to Margaret Ramsey and Thomas was married to Elizabeth Rock.
I would love to know more about the McAlonan's that you have history on, as if we could make a connection between them it would help me greatly with my family history.