The father of British snowboarder Ellie Soutter who died on her 18th birthday believes she could have been struggling with the pressure of competing in high-level sport.
Tony Soutter told BBC South East he had lost his best friend, his "total buddy" and his rock.
Ellie "wanted to be the best" and not "let anybody down", he said.
UK Sport said it was working with partners to provide appropriate support for athletes.
'One little thing'
Speaking publicly for the first time since his daughter's death on 25 July, Mr Soutter said he believes his daughter's history of mental health issues coupled with the pressure of elite performance may have contributed to her ending her life in Les Gets in the French Alps.
"She wanted to be the best," he said. "She didn't want to let anybody down.
"Unfortunately it all came about from missing a flight which then meant she didn't go training with the GB squad.
"She felt she'd let them down, felt she'd let me down and just tragically it just takes one silly little thing like that to tip someone over the edge, because there's a lot of pressure on children."
Calling for action to help other young athletes, Mr Soutter added: "Mental health awareness needs to be really looked at and made more public."
He said: "I have lost my best friend, my total buddy. She was my rock."
Soutter grew up in Oxted, Surrey, before moving to the Alps where she trained.
Her bronze was Team GB's only medal at the Youth Olympic Winter Festival in Turkey last year.
Her family have set up a foundation in her name to help young winter sports athletes needing financial support.
The Samaritans provides advice on what to do if someone finds they are struggling themselves or sees another person having difficulties.
'Great talent lost'
A spokesman for UK Sport said: "This is a desperately sad situation and our thoughts are with all of Ellie's family and friends.
"We are working with all of our Olympic and Paralympic programmes and the mental health charity Mind to make sure appropriate support is in place."
A statement issued by British Ski and Snowboard said: "Ellie was an incredibly popular and well-liked member of the team and the country has lost a great talent.
"The wellbeing of all athletes across every discipline is the primary concern of any sporting organisation.
"We commend the family for setting up the Ellie Soutter Foundation and they have our full support."
Bill Sweeney, CEO of the British Olympic Association, said:"Our thoughts remain dominated by the tragic and untimely loss of Ellie Soutter, who was an incredibly popular member of the European Youth Olympic Festival team in 2017.
"We recognise the pressures that come with elite sport, and during the time athletes are with us at a Games we ensure there are mechanisms in place for athletes and staff to speak confidentially to pre-identified welfare officers.
"Our thoughts are with her family at this time."
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