A teenage racing driver who had both legs amputated after a crash at Donington Park has said his sister has been his "one true hero".
Billy Monger, 17, was airlifted to hospital after crashing with another car on the track mid-race on 16 April.
From hospital, he posted on Facebook that Bonny "gave me the will to keep fighting" and thanked everyone for their "love and generosity".
A campaign to raise money for his future has raised more than £750,000.
Billy, from Charlwood in Surrey, wrote the support he had received from fellow motor racers, fans, and everyone has been "awesome and truly inspirational".
"Your kind words have given me and my family the strength to get through this past week," he posted from the Queen's Medical Centre in Nottingham.
The Formula 4 driver also said that without emergency crews at the Leicestershire track and medical staff "I wouldn't be here today".
"I will always thank you all for saving my life," he said.
"The one true hero of this tragic event has been my sister, Bonny who gave me the will to keep fighting.
"A value that I will continue to hold now... and for the rest of my life."
The Just Giving page was set up by Steven Hunter, head of Billy's team Derbyshire-based JHR Developments, to help the 17-year-old "return to a full and active life".
The donations came in swiftly, including one from Formula 1 driver Jenson Button and F1 driver Max Verstappen, who both donated £15,000.
Billy's F4 former rival Devlin DeFrancesco made a donation of £26,000.
Hundreds of people have sent messages of support to the teenager and a hashtag, #billywhizz, has been widely shared on social media.
Billy was competing in the Formula 4 British Championship, a motor racing series which features a mix of professional motor racing teams and privately funded drivers.