I am intrigued with the combination of Robert Kennedy and Campbell Kennedy in your post. My 4th great-grand father was Robert Campbell Kennedy (1762-1815). His parents were William Robert Kennedy and Martha Campbell. I have a documented line on these 3 people, but outside of the 3 of them I only have undocumented info. I am not sure where William and Martha were born. Robert Campbell Kennedy was born in Augusta County, VA; fought at Kings Mountain in the Revolution, and died in Lincoln County, TN.
In the undocumented notes I have, there is a possible list of siblings of Robert Campbell Kennedy. They include the oldest child, John Kennedy (b. 1757, VA; m. Rachel Campbell d/o Jacob and Jane Campbell). I have only one child listed for this couple, James (b. 1775, VA).
If you think this would help, I can give you the sources where I have found it along with some more details...NOT documented by me...on William Robert and Martha. I found this info while I was looking for another family line and noted it for future work that has yet to be done.