(CNN) The call Army veteran Miguel Perez had been waiting years for came Friday. It was from immigration officials who phoned his attorney so see how quickly Perez could come to downtown Chicago to take his oath to become a US citizen.

Just two months ago, Perez doubted this day would ever come. He had been stripped of his green card and deported to Mexico, despite his military service that included deployments to Afghanistan.

But his history also included a felony drug conviction in Illinois and a prison term of more than seven years.

He was sent back to Mexico, the country he left when he was 8 when his family came to the United States so his father could pursue a soccer career.

Things changed two months ago when Illinois Gov. J. B. Pritzker granted Perez clemency for his conviction. Attorney Chris Bergin and Perez took it as a new argument for Perez's citizenship.

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