More doubt has been cast on whether Meghan Markle's father will attend his daughter's wedding to Prince Harry on Saturday, as it is reported he is due to have heart surgery, BBC reports.
Thomas Markle had told US website TMZ he would not go amid a row over paparazzi photographs; then that he would; then that he could not, due to a planned heart procedure.
Kensington Palace declined to comment.
Ms Markle's estranged half-sister said he had faced an "unbelievable stress".
Speaking to Australia's Sunrise morning TV programme from Orlando, Florida, Samantha Markle said she was not sure if Mr Markle would be travelling to Windsor.
"He sent me a message that he was undergoing heart surgery," she said.