Official state newspaper Granma said that Fidel Ángel Castro Díaz-Balart, also known as “Fidelito”, had died following months of treatment for depression.
Part of the treatment included hospitalisation, the paper said.
His father Fidel Castro, a revolutionary turned longserving leader of communist Cuba, died in 2016. Mr Díaz-Balart is believed to be one of several children that Mr Castro fathered with multiple different women.
He was born in 1949 after his mother, Mirta Díaz-Balart, married a young Fidel Castro who was still years away from leading in insurrection that toppled the government of Fulgencio Batista. She was reportedly the only woman that Mr Castro ever married.
Ms Díaz-Balart returned to Cuba over the years to visit her son after having moved to Spain.
Mr Díaz-Balart served for a time as head of Cuba’s nuclear power programme, according toThe Miami Herald. He was fired from that position by Fidel Castro himself, the Daily Beast reported.
“There was no resignation,” Mr Castro reportedly said. “He was fired for incompetence. We don’t have a monarchy here.”
Mr Díaz-Balart had studied nuclear physics in the Soviet Union, a key patron and ally of Cuba after the country's Communist takeover.
More recently he was a scientific advisor to the Council of State and Vice President of the Academy of Sciences of Cuba, Granma said. PLACE YOUR TEXT ADVERT BELOW:>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> How I Made Me =N=2.5 MILLION In 7 Days from 2 Common Product I Imported and how you can do the same. Click HERE FOR FREE Details right now Warning To Men: This 3 Foods Is Killing Your Erection. Click Here To Know Them Secret Fruits that increased my Manhood and makes me last 55 minutes+ all time - Click here to get it Warning: Got Arthritis? 3 Simple Ways To Get Cured And Be Permanently Free From Joint Pains. Click Here To See Them REVEALED!! Reduce Your Blood Sugar Level And Reverse Diabetics Within A Short Period Of Time. Click Here To See How MIDNIGHT,Pressed Mr Kilanko Suddenly Couldn't Urinate. Shrink your Enlarged Prostrate Here! Click Here Now