All Canadians need a passport to travel abroad, even if they are newborns or small children.
Under Canadian passport rules, either parent or guardian can legally apply for the child's passport. This means a non-custodial parent could possibly acquire a passport for a child, then take them out of Canada without the knowledge or permission of the custodial parent.
Passport Canada states "both parents are requested to participate in obtaining passport services for their child and to sign the application form. The other parent may be contacted. To avoid possible delays, we strongly recommend that you provide a long-form birth certificate showing information on both parents. Where a legal guardian is the applicant, the other legal guardian as the case may be is also requested to participate."
"Where a court order or agreement exists referring to custody of the child, only the person with custodial rights may apply. All documents that refer to custody or mobility of, or access to, the child must be provided. If a divorce has been granted, a copy of the divorce judgement or order must also be provided. Where joint custody provisions exist, either parent may apply."
Click here for a passport application for children.