Yes Carlo and Paolo Gambino were both Illegal aliens. I believe their brother Gaspare was the only legal U.S. citizen of the Gambino brothers. Robert Kennedy actually tried to deport Carlo twice. Carlo had money and used the Canada entry way, but not properly. His case was still going on up till the time of his death.

"I have this Nightmare. I'm on 5th avenue watching the St. Patrick's Day parade and I have a coronary and nine thousand cops march happily over my body." Chief Sidney Green