My family and I are traveling next month from Paris to Mürren on a Sunday afternoon. We will be changing trains in Strasbourg and Basel before we get to Interlaken. Our connection time in Interlaken is fairly tight for the train we'd like to catch to Lauterbrunnen. Can we purchase our tickets for connections from Interlaken-Lauterbrunnen-Grütschalp-Mürren anywhere in Switzerland--such as on our layover in Basel? Or can Interlaken-Mürren tickets be purchased at anytime at a ticket kiosk? Also, if we want to purchase Junior Travel Cards (for our kids ages 6, 11, and 12), does that need to be done in person at a train station?
Finally, I've read in this forum where parents must have some kind of Swiss travel pass to purchase Junior Travel Cards. The SBB website just states that children with a Junior Travel card must be accompanied by a parent who holds a valid ticket. Can someone clarify this?
Thanks so much!