An 18-year-old Chicago boy died just hours after a final reunion with his parents who were detained by Immigration and Customs Enforcement (ICE) trying to cross the US-Mexican border to get to him. 

Kevin Gonzalez sadly passed away Sunday at his family home in Durango, Mexico, following a diagnosis of stage 4 colon cancer late last year. 

Gonzalez learned he had terminal cancer over the Christmas holidays while visiting his brother in Chicago, the city where he was born. 

When his family were told he was dying, Gonzalez's parents told ABC13 that they applied for emergency visas to see him, but were denied because they had both been previously deported. 

In a desperate attempt to see him, the parents, Isidoro González Avilés and Norma Anabel Ramírez Amaya, then decided to cross the border illegally. 

Gonzalez's parents were caught crossing in Arizona and were detained on April 14, sparking a month-long fight to get to Kevin as he underwent cancer treatment in Illinois. 

The family's attempts to enter into the US under the Trump administration's hardline immigration policies failed, and with just days left to live, Kevin eventually left the US to find his remaining family in Mexico. 

Gonzalez checked himself out of the University of Chicago Medical Center last week, despite his parents still being in Immigration and Customs Enforcement (ICE) custody at the time. 

Gonzalez flew to his grandmother's home in Mexico with hopes that his parents would be released by ICE and deported in time for him to say goodbye. 

His prayers were answered last week, when an Arizona judge on Thursday ordered Gonzalez's parents to be released after weeks in detention. 

They returned to Mexico on Friday, and officials helped them board a bus from the border to an emergency flight to get to their son as soon as they could, his brother Jovany Ramizrez told WLS-TV. 

The family were able to reunite just in time, as Kevin's parents arrived at the home in Mexico to spend one final weekend with their son. 

Footage of the family's embrace showed the weak patient hugging his parents and siblings as they were finally together again. 

He passed away on Mother's Day on Sunday, surrounded by his family. 

After reuniting with his son, Aviles told CNN: 'We managed to make my son's dream come true.' 

'To be with him again, to love him, to give him the love we could not give him during these months when he was not with us,' he said. 

Crying as she held her son, Amaya added: 'These tears are from emotion, from seeing him again, from touching him again, from telling him how much I love him.'  

Shortly before reuniting with his parents, the 18-year-old told CNN that he was thankful for the help his family received in their desperate scramble to see each other again. 

'What I want to say to people is thank you for helping my family to be able to have the choice,' the cancer-stricken teenager said. 

Department of Homeland Security (DHS) officials said the parents had applied for B1/B2 visas, which grant temporary non-immigrant status, but rejected them 'due to their previous unlawful presence and entries into the United States.' 

Despite being blocked for weeks with time running out, Aviles said he and his wife would have stopped at nothing to try and get back to their son. 

'We sought every option. They denied us visas. They detained us at the border,' he said. 

DHS said Kevin's father had been arrested and charged numerous times over the years, and was deported in 2011. It is unclear what crimes he had previously been charged with. 

Aviles described himself as a 'humble worker' who had found a job a as a taxi driver and truck driver in Durango, and decried that he and his wife were treated 'like criminals' in ICE detention. 

'We went through a lot, and in the end, all I want is to be with him,' he said. 

Rep. Delia Ramirez, a Democrat representing the area of Chicago where Kevin was receiving treatment, slammed the Trump administration's efforts to keep the family apart before their final reunion. 

'Rejecting visas to Kevin’s family did not protect our communities,' she said. 

'Putting families through the pain, stress, and fear of separation is not making our loved ones safer. Detaining immigrants for months in for-profit, inhumane detentions is not securing our nation.'