Mr Motivator’s 12-year-old granddaughter Hadassah has died after battling meningitis for five days.
The exercise guru – who became a cult figure on British TV after starring on breakfast show GMTV in the 90s - said she died in the early hours of Thursday in Antigua.
Hadassah lived on the island with her mum Caroline Evans Charles, who is Mr Motivator’s daughter.
“It’s not meant to happen like this,” said the 69-year-old, who is thought to have had a very close relationship with his granddaughter.
“The circle of life dictates that parents and grandparents go first.
“You are not supposed to bury your child or your grandchild.”
The fitness star, whose real name is Derrick Evans, went on: “We have to fight on no matter what.
“I want to remind everyone to tell your loved ones every day how much you love them.”
According to the PA news agency, the health coach's wife Sandra has flown to Antigua to be with the family. He is set to join her.
Mr Motivator was born in Jamaica and moved to the UK in 1961.
Last year he joined BBC television's HealthCheck UK Live to "keep Britain fit" amid the coronavirus pandemic and lockdowns.
The NHS says meningitis "is an infection of the protective membranes that surround the brain and spinal cord (meninges)".
It can affect anyone, but is most common in babies, young children, teenagers and young adults.
Additional reporting by PA.
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