My family and I once spent a month in Italy and survived with only one suitcase. Our youngest was two years old at the time so rather than pushing around a piece of luggage, I knew my hands would instead be pushing around a stroller. Our oldest was six and not quite ready to trust with his own bag – so to keep things easiest, each of us had a carry-on of some kind (backpacks for the three of them, a tote for myself) and everything else was in one shared suitcase.