Looking for Kearney in Lower Drumgooland

Does anyone know history of Kearney settlement in Drumgooland.  None are among most numerous Gaelic families in 1659.  A number live in Drumlee in Griffiths and no where else in Down.  I have also noticed that there seem to be Kearney associations on the eastern peninsula of Down.  Does anyone know if there is a connection between the familieis in the two localities?  Our ancestor seems to have been in between around that time, in Killyleagh Parish.  John, b. ca. 1836 of William, b. ca. 1815, married into the Moreland family whose female line descent was Killeen.  I would very much appreciate some  hint of how John arrived in Killyleagh.  Also, no matter how I search, I can't get a handle on how the few Kearneys in evidence even got to Down.  From the North?  From the Isle of Man?  From Offaly and Meath?  Unfortunately, no father to son continuity came into the present to test dna.  If anyonce could help me know  how to trace this movement of the family surname to Down and around Down I would be very grateful  Thanks.