Under a cloudless winter day, Ali Hassan carried his son's small body to bury at an Islamic cemetery in California's Central Valley.

"I'm a U.S. citizen; my son is a U.S. citizen," the 22-year-old father told mourners at a service before burial. "The Muslim ban kept my wife from coming to the U.S. for over a year. It forced me to choose between my son's health and keeping our family together. We are angry, but we know our son did not die in vain."

The child's distraught mother mourned privately at home.

Abdullah Hassan died Friday at UCSF Benioff Children's Hospital in Oakland, where his father brought him in the fall to get treatment for a degenerative brain condition. He had been on life support when his 21-year-old mother, Shaima Swileh, arrived last week.

Hassan spent his youth in California's central valley after his family immigrated there from Yemen. During a trip to the warn-torn country in 2016, he fell in love with Swileh and married her that same year.

Because she is Yemeni, Swileh was restricted from traveling to the United States under the White House travel ban that's keeping citizens from Yemen and four other mostly Muslim countries from entering the country.

The family stayed in Cairo, Egypt, while Swileh tried to obtain a waiver to that ban, which would allow her a visa to travel with her family to the United States to receive medical treatment for the boy. But she was repeatedly denied travel documents, Hassan said.

When Abdullah's health worsened, Hassan went ahead to California in October to get their son help. As the couple fought for a waiver, doctors put Abdullah on life support.

"My wife is calling me every day wanting to kiss and hold her son for the one last time," said Hassan, choking up at a news conference earlier this month.

He started losing hope and was considering pulling his son off life support to end his suffering. But then a hospital social worker reached out to the Council on American-Islamic Relations, which sued on Dec. 16, said Basim Elkarra, executive director of the advocacy group in Sacramento.

The State Department granted Swileh a waiver the next day, and she has since received a visa to stay in the country.

She was pictured cradling her son in the hospital 10 days ago.

"With their courage, this family has inspired our nation to confront the realities of Donald Trump's Muslim Ban," said Saad Sweilem, a lawyer with the council who represents the family. "In his short life, Abdullah has been a guiding light for all of us in the fight against xenophobia and family separation."

Hassan said he hopes his family's struggle will lead to policy changes and families like his will not have to separate.