Which suitcase you want to use will depend heavily on a couple factors. If you will be traveling with another parent or older children who can help with the luggage, or if you will simply be driving or flying straight to one destination, you will want to find a large but lightweight rolling suitcase.
I would look for one that is expandable (as you will likely buy souvenirs. Even if you don't, baby items expand during travel. It's uncanny). You want to look for a suitcase that rolls and with bars that can handle a second bag (such as a duffel or diaper bag, or even a car seat bungied onto it) for airport travel. Here are some ideal choices, all of which are roomy yet extremely lightweight:
If you will be traveling as the solo adult, however, having your hands free will be crucial. You very well may need to carry your bags on your back while lifting baby and stroller as you dart up and down stairs at a train station. Here are perfect hands-free bags for single adults traveling with little ones:
- High Sierra Transport with detachable day pack
- Centerline Grand Voyage 90L