Hi Big Red L,
Be careful if you take a car baby seat for use on the aircraft. Airlines have strict rules on what can and can't be used, and just to be helpful US registered airlines have different rules again. The child will have to sit on your wifes lap otherwise. Car seats are okay in the cruise at our airline. We also would not be allowed to assist by carrying your baby, down steps etc. but the crew can carry your bags if needed. When you know what airline your travelling on it's a good idea to check out their specific web-site as some place greater or lesser restrictions.
Quite often we have passengers who come off Trans Atlantic flights and they find rules on European airlines are quite different.