I will soon be visiting Canada for the first time, as part of a multi-stop journey with my daughter. I bought a one-way ticket for the leg from Canada to Europe and the (Canadian) agent pointed out the requirement to have a notarised letter from my daughter's mother consenting to her travelling with me alone. The T&Cs accompanying the ticket confirmation set out the requirement.
This is the first time I have encountered such a requirement. My question is whether the requirement is really necessary - how often do the Canadian authorities actually ask to see this letter, and how difficult would things be if I were not able to produce it?