My parents have 10-year visitor visas, they have been visiting me a few times. I usually buy 2-way tickets for them and the maximum time they stay in Canada is 6 months. This time, because I don't know when they will come back home, so I only bought the 1-way tickets for them. My parents are all over 65 years old. Do you think if they will be rejected at the Toronto airport? Really appreciate your answer.