12 hour train ride.

So on the 15th of march, my two boys and I are taking a 12 hour train ride to visit my big sister. My oldest will be 34 months and my youngest will be 9.5 months. The train leaves at like 9 at night and doesn't get there till the next night. I'm not too sure what to expect as I've never been on a train and never traveled alone with my kids. My almost 3 year old is very energetic and can't stay still for too long so I'm kind of nervous about that. Any advice or experiences with traveling with little ones in general and on a train would be greatly appreciated  

Bring toys, snacks, coloring books.