Trains or planes for travel for Paris and Italy

Your original travel route sounds good. Your second one would require some backtracking (more time and money).

Take the train everywhere with the exception of your day trip from Florence to Siena. For that route the bus is a better choice because it takes you into the city. The train station is outside the city.

Your best train choice for Venice-Paris is the direct night train. I'm guessing that you could get by with a 2-bed rather than a 3-bed sleeper and have your baby sleep on the floor. However, you should find out if you have to book a bed for the baby. This a popular night train so accommodations can sell out weeks in advance. Since the Trenitalia site doesn't accept US credit cards for online booking, you'll need to book with Rail Europe. For all your other trains just buy your tickets when you get to Italy. The station ticket machines do accept US credit cards.

Even though I prefer trains to planes when feasible and sleep well on night trains, I need to tell you that flying on a budget airline from Venice to Rome will be much cheaper than the night train. A good choice would be easyJet from Marco Polo to either Orly or CDG.

Traveling with a baby will be much more comfortable and relaxing on the train than on a plane; consider paying a bit more for 1st class. If you do decide to train from Rome to Paris you could stop over at the CT on your way to break up a long ride into shorter segments. You won't need a car anywhere, but with the baby it might be wise to give yourself a break and grab a taxi occasionally rather than the bus/metro, especially in Rome.

Awesome! You are spot on.

Does the current line up sounds good, or should we go from Venice to Florence, Rome and then CT? Since both Venice and CT would be relaxing, I would rather relax after a lot of walking in Rome and before heading for more to Paris.

Any good links to search for accomodation in each of these cities?

Traveled by train last summer: Milan --> Venice --> Florence --> Rome.

The trains between Italian cities are very convenient and fast, and most train stations are centrally located. One problem with trains, though, is storage. My husband and I each had a suitcase and carry-on, and it was tough finding enough space in luggage racks on each ride. Once my husband had to leave his suitcase on the entrance platform and keep checking on it, and another time a nice nun lent us some space near her seat! Telling this story because you might want to keep that in mind with a baby and all of his/her supplies to carry around, but don't see how it would be easier on a plane. Pack light!

Definitely do not need a car in any of the Italian cities. Good metro and bus systems, and there are tours for day trips. I would not have wanted to worry about parking in Italy, especially Venice, where cars aren't allowed in most areas.

Thanks to everyone who has replied with so much information. I believe I have the information now I was wondering about. Will be back for more about where to eat and sleep in these places!

Ciao