Bradley Lowery, a boy who struck up a close friendship with England striker Jermain Defoe after being diagnosed with a rare cancer and gained fans across the sport, has died. He was 6.

Bradley’s family said Friday in a statement on its Facebook page that he died in the arms of his mother and father.

The statement said, ‘‘He was our little superhero and put the biggest fight up but he was needed elsewhere.’’

Bradley, who had neuroblastoma, was picked to walk out with the starting lineup of then-English Premier League team Sunderland several times last season, and formed a bond with Defoe, who now plays for Bournemouth

‘‘He will always be in my heart for the rest of my life,’’ Defoe said the day before Bradley died.

Bradley also walked out with the England starters for a game at Wembley Stadium in March, and supporters of different clubs made banners and chanted his name at games.

Sunderland said in a statement: ‘‘Bradley captured the hearts and minds of everyone at our club with his indomitable spirit, tremendous courage and beautiful smile, which could light up even the darkest of rooms.

‘‘Despite battling neuroblastoma for much of his all too short life, he demonstrated a bravery and fortitude beyond his years that humbled us all. He was truly an inspiration.’’

Soccer fans had hoped a massive fund-raising effort last year could get him to the United States for pioneering treatment, but Bradley’s family announced in December that his cancer was terminal.

World soccer’s governing body FIFA tweeted: ‘‘Today, the football world lost one of its bravest fans.’’