The Williamson's of Tullylish

I'm looking for information about the Williamson's of Tullylish. My 5th great Grandfather was John Williamson 1780-1864. He owned land in the townland of Bleary in 1810. I know he had atleast 2 sons maybe 3. My 4th great grandfather also John, born in Bleary in 1810 and David born in 1812.  He also had a brother Richard Williamson 1799-1893 and a brother David. There is a double marriage in the parish of Tullylish,  Church of Ireland of a Richard Williamson and Rebecca Doke and a David Williamson and Catherine Nicholson both on May 20, 1820.  There are also many Williamson baptisms in the Tullylish parish records. If anyone has more info or are still living in Ireland and are descended from the Williamson's of Tullylish I would love to hear from you. I live in Ontario, Canada.