1900 Midland & Drayton Townships, Drayton town, Pembina, North Dakota census (taken June 26th and 19th)
Dwelling 225, Family 226
James Devlin, head, born May 1834, age 66, married 41 years, born French Canada, father born Ireland, mother born Ireland, immigrated 1880, farmer
Ruth Devlin, wife, May 1840, 60, 12 children living out of 13 born, English Canada, England, England
Hattie Devlin, daughter, May 1874, 26, single, French Canada, Canada, Canada
William Devlin, son, August 1880, 19, single, North Dakota, Canada, Canada, farmer
Maggie R Devlin, daughter, Oct 1882, 17, North Dakota, Canada, Canada, at school

Dwelling 135, Family 136
James Devlin, Jr., head, born March 1860, age 40, married 12 years, born French Canada, father born Canada, mother born Canada, immigrated 1880, farmer
Elizabeth Devlin, wife, June 1864, 35, 6 children living out of 6 born, French Canada, Ireland, Canada, immigrated 1882
Walter O Devlin, son, June 1889, 10, North Dakota, Canada, Canada, at school
James R Devlin, son, Nov 1890, 9, North Dakota, Canada, Canada, at school
Sadie M Devlin, daughter, July 1892, 7, North Dakota, Canada, Canada, at school
Iva J Devlin, daughter, Jan 1894, 6, North Dakota, Canada, Canada, at school
William L Devlin, son, Jan 1897, 3, North Dakota, Canada, Canada
Lawrence Devlin, son, April 1899, 1, North Dakota, Canada, Canada

If the James R Devlin (above) is the father of Leo, then perhaps the birth year you have for Leo is too early.

I have not found any of these folks in the 1911 Canadian census.