Can chicken-pox, MMR and hepatitis a vaccine all be given on the same day to a 1 year old baby?

Vaccines. Yes, all three vaccines can be given on the same day. All three vaccines are are safe and side effects are minimal.
Absolutely... When your baby is out in public, e.g., at a store, his immune system is bombarded by dozens of germs, some of which are potentially harmful. Yet, it is able to fight off those germs and strengthens itself to handle them even better the next time. Here we're talking about 5 inactive (or weakened) germs, given on purpose in a controlled manner in order to train the immune system. Piece of cake!