People : Ida O'brien to James O'brien
Inez O'brien 2 people
Irene O'brien 13 people
Iris O'brien 3 people
Isabel O'brien 3 people
Jack O'brien 15 people
Jaclyn O'brien 5 people
Jacob O'brien 3 people
Jacqueline O'brien 19 people
Jacquelyn O'brien 3 people
Jaime O'brien 3 people
Jake O'brien 2 people
James O'brien 301 people