Farulla is a surname o Sicilian origin. Perhaps this surname originate in the so called "interior Sicily", the ENNA area, especialle in the municipality of PIETRAPERZIA. now the majority of the sicilian FARULLA live in FAVARA, near AGRIGENTO and in PALERMO.
AIRO is also a Sicilian surname of the area of AGRIGENTO. it is very very rare at the moment. But this surname could also be of finnish origin.
The origin of these two surnames is obscure, they could come from an old nickname.