+———William MCELROY
          |
      +———Robert MCELROY (16 Mar 1856 Ireland – 16 Jan 1916)
      |
  +———Robert Arrol “Arrol” MCELROY (27 May 1898 R. M. of Pembina, Manitoba, Canada – )
  |   |    
  |   +———Mary Elizabeth “Elizabeth” MORRISON ( – 1946)
  |    
  Charles MCELROY 
  |    
  +———Dorothy Anne SOUTHWORTH