Hello, my family will be visiting Switzerland in March and have one day of train travel planned, Tirano to Zurich. I am planning to purchase 3 saver day passes for members of the family older than 18, but I was going to buy a child’s day pass for my 15 year old. I want to make sure the child’s day pass is valid without any of us having a travelcard or other discount cards or passes, just the adult saver day passes. Thank you for your help.