Late casino tycoon Stanley Ho's fourth wife Angela Leong has come out for the first time to clarify the situation over his mysterious 17th son - who was widely believed to have died in childhood.

In a Chinese statement issued last Saturday, she "solemnly introduced" Mr Ho Yau-bong, her son with Mr Stanley Ho.

Mr Ho Yau-bong has never appeared in public.

Ms Leong, 59, is the managing director of SJM Holdings, the company which owns many of Macau's casinos. She said this was her first and last time clarifying the issue.

"Because of health reasons, the family has never released any information on him. But due to Stanley Ho's passing, Yau-bong's name will be carved on his father's tombstone in accordance with tradition."

She did not specify Mr Ho Yau-bong's age or any health issues.

Mr Stanley Ho died aged 98 last month. Even a statement from the Ho family after his death did not include the name of Ho Yau-bong.

Mystery has shrouded this son, who was rumoured to be named Ho Yau-kai. Various explanations of why he was never seen with the family surfaced - the most common and widely believed story was that he had died in childhood.

Ms Leong said in her statement: "As a mother, I was anxious that rumours would negatively affect Yau-bong's mood. It's hard to be an ordinary person in such a family, but as a mother, I hoped that under our protection, he could feel the safety and kindness of the outside world."

She said Mr Ho Yau-bong was never a secret among the extended Ho family and said "he needs to be protected, not disturbed".

This means the gambling tycoon has 15 surviving children - five of them by Leong.

Two of his children by his first wife Clementina Leitao - Robert and Jane Ho - had died before their father in 1981 and 2014 respectively.