This post is based on Canadian Government’s information. “I am travelling with my minor child without my spouse. What documents must I present?”
So when one parent travels with minor child without the spouse. He/She must have the following documents:
You must present the following documents:
1: A copy of the child’s birth certificate
2: A letter of authorization signed by the parent who is not travelling, containing their address and telephone number, in English or French if possible, and
3: A photocopy of the non-accompanying parent’s signed passport or national identity card
For more details information, please read Canadian CIC official website.
Canadian Government also provided a consent letter template here.