Fiorella's loft apartment is very cozy, a better alternative to just a hotel room, especially for a family, as you get a small home for your amount of nights to stay, with a small but all-equipped kitchen (we've missed only the kettle) and normal-size bathroom.
The two particularities I would advise the families to take into consideration is that if you plan your stay with a small child there is the floor with ceramic tiles, which is quite cold, so don't forget to take socks or slippers. And it can be quite noisy if you are a light sleeper, like myself. Though we were so tired after our walking around Rome that it almost didn't bother us ))