Niamh O'Brien, a former lead Irish dancer and the wife of Riverdance creator Michael Flatley, died peacefully at Beacon Hospital in Dublin at the age of 52.
Her passing followed a period of illness, according to statements from a family representative and relatives.
O'Brien built a successful career in international dance productions before marrying Flatley in 2006.
The couple raised one son, Michael St James, who was born in 2007.
Before turning professional on stage, she competed at the highest levels of Irish dancing and finished fourth at the world championships at age 17.
Michael Flatley Announces Wife's Death
Flatley announced her death on social media, sharing photographs that spanned her career and personal life.
"My heart is broken. I have lost my beautiful wife, Niamh, and my best friend.
My gorgeous bride of twenty years has gone to the Lord in Heaven," he said.
The dancer and producer also thanked supporters who offered condolences after the news emerged.
"She was the most loving mother, wife and person, and our lives will never be the same without her," Flatley said.
"Thank you for all the love and kindness you have shown us. Please keep Niamh, Michael St James, and out family in your thoughts and prayers."
Flatley had previously spoken about plans to renew their marriage vows for their upcoming 20th anniversary.
"I have something very special planned for the 20th to renew our vows. I shouldn't have just said that, my wife is going to know all about this!
But I won't say what it is and I won't tell her. I'm the luckiest guy in the world," he said.
He also reflected on the strength of their marriage in earlier comments.
"Marry the right person. I'm very blessed, I'm in love with my wife, who's in love with me.
We have a wonderful son. I don't remember us ever having a bad word," Flatley said.
A spokesperson for the family addressed her medical care and asked for privacy on behalf of both relatives.
"The Flatley and O’Brien families are devastated by Niamh’s sudden passing and have asked that their privacy be respected as they come to terms with this heartbreaking loss," said a representative for Michael Flatley.
The family acknowledged the medical team involved in her hospital care during her final weeks.
"They express their sincere gratitude to the doctors, nurses and staff at Beacon Hospital who cared for Niamh over the past few weeks, and to everyone who has offered their kindness and support to the family," the representative added.
Funeral arrangements and service details will be released in due course by the family.
