1.what do you man by local transport? Bus-tram is NOT included. However, many touristy towns in the Swiss give their guests free passes for local transit-limited area.

Also note that the pass is NOT valid-will only give discount-on the private upthemountains railways south of Interlaken-making them expensive in stead of very expensive. You do not need to activate passdays for that-just show pass when buying hese tix-they have seen it zillions of times there. There may also be more local ticketing options-these may vary with season.

Further possible discounts are shown in country info. Do not expect too much from that though-except these discounts on some other railways (Swiss has 40-50 different ones)

2.YOu can take on trains anything you want/like, as long as its not too bulky and its very common to see parents with (very) young kids.

Please read the items about reservations on this site! All your journeys as far as the Swiss border require reservations (and supplements). You didn’t say when you are going but Eurostar passholder fares sell out sometimes weeks in advance! The same can be true for the direct trains (Thalys) from Amsterdam to Paris. Going to Amsterdam you have the option of going to Bruxelles by Eurostar (if passholder fares are available) and changing or taking the boat from Harwich to Hoek van Holland. From Amsterdam to Paris there are other (slower) options if the direct trains are fully booked. Experts on this site can advise if you need help.