We booked a tour of Ireland this summer with another couple. We used a travel agency that included our flights. We are booked on United on the outbound and Air Canada on the return trip. All four of us are retired and we'd like to sit near each other. Well we were able to get seat assignments for the outbound and the return from Dublin to Toronto however we can't get seating assignments on the Toronto to Minneapolis leg (our destination). I spoke with Air Canada and they informed me that we could only get seat assignments one day before travel or at the airport. They said it is because we are on a United ticket that they can't assign seating. My wife is an anxious flyer and she really needs to sit near me and I'm afraid that if we wait we'll be in different locations on the plane. I understand that Air Canada requires payment for seating and we're willing to pay to ensure our seats but they still say we have to wait. Our travel is in August. I've emailed Air Canada's customer service, VP Customer Relations, Director of Customer Relations and even their CEO and haven't heard back. This seems like an unusual policy and frankly ridiculous. Any help or advice would be appreciated.