Looking for cousins descended from Samuel McDonald 1830-1906 Ontario

Samuel had 9 children.  I am descended from the youngest Malcolm "Mac" Arthur 1870-1946.  Have found 3rd cousins descended from other siblings but looking for more for a potential reunion.  Other siblings were: Alexander Grant 1853-1897; Elizabeth "Liddie" 1855-1931; Harvey 1857-?; Annie Nancy Locke 1859-1926; Hattie Harriet Emma 1863-1942; John Samuel 1864-1941; Jesse 1866-1941; Benson Smith 1868-1929.

Any help is appreciated.  THANKS