Bovino Lambo
It is a fact the cow-child is a coward and a crybaby. Some people would try to lighten up his mood... some, would do the opposite. It would always end up with them bribing the child in many ways e.g. grape candies, sweets and Maman's cooking. However, if he still refuses, then that means he is really hurt. If you're the one who brought tears into those orbs, be ready to face the wrath of two innocent looking girls, a very naïve mother and pissed off brother figures (plus a hitman).
Lambo, no matter how annoying he can get,is still the youngest Vongola guardian. This automatically makes him the "baby" in the Famiglia.