He earned a master's degree from the Johns Hopkins University School of Advanced International Studies as an Armed Forces of the Philippines Scholar.

[5] His eldest sister, Celerina Gotladera, served as the Chairman of Civil Service Commission and Mayor of Bulan, Sorsogon.

[5] Gillego was often interviewed by American and western media to expose Marcos' fraud, particularly with his military medal decorations.

[8] Through his writings and countless interviews with the American press, Gillego publicly questioned Marcos' war record.

[9] In 1986, he served on the Commission on Good Government[10] on behalf of President Corazon Aquino to find real estate holdings of the Marcoses in New York.