Cameron Monaghan was born in Santa Moncia to his single mother, Diane Monaghan. He has been acting since 2002. He made severals films such as The Music Man, Click. He also made a special and guest appearance on several television shows such as Malcolm in the Middle, Criminal Minds, Numb3rs, The Menalist, Three Rivers, The Glades, NCIS, Rizzoli and Isles, Terriers, Fringe and Law and Order: Special Victims Unit. He also was in the 2011 film Prom.
In the televison show Shameless Cameron Monaghan has portrayed character, Ian Gallagher. He has played the role since season one and contiuining into season four. He has been critical acclaimed for his role.