Gabby Logan said she assumed “a lot of responsibility” following her brother’s death at the age of 15.
The 49-year-old presenter, who became one of the first female sports anchors to break into terrestrial television, said the tragedy also led her to “take chances” including an early start in radio.
She said: “He was a beautiful, strong, fit, healthy, handsome, popular young man and he had everything to live for.”
Daniel died of hypertrophic cardiomyopathy, a disease which affects the heart’s ability to pump blood around the body, just after he signed to be a professional footballer for Leeds United.
Logan said on the Sunday programme: “As the eldest child, I think I assumed quite a lot of responsibility, I went and picked up his death certificate, for example.”
She said “everyone deals” with grief differently as she said her mother, Christine, sought help through counselling and looking into religion.
Logan added: “My dad was very much a person who felt the glass was half empty already and for him, this was confirmation that life was no good and he kind of pulled himself away from a lot of our family life.”
She also said: “I went to Durham (University) and I thought right, every day is for grabbing hold of and doing things and trying things and yeah, I’d like to work for the radio station in Newcastle.
“I attacked my university life with with that kind of energy, I suppose…but I think in my heart I kind of felt like he’d not had that chance and I was (going to) take it.”
Logan chose Sir Elton John’s Daniel as one of her songs to take to the islands as a castaway on the BBC show.
When she was a teenager, Logan said she “loved” competing as a rhythmic gymnast for Wales.
Reflecting on that time, she said: “I did you know, navigate a little bit of, I suppose an eating disorder in terms of not eating enough because I wanted to retain a pre-pubescent body but it gave me a sense of what my body was capable of and that was doing a sport that I loved.”
Her eating habits, she said, returned to normal after she retired from the sport in 1991.
After university, Logan would go on to join Sky Sports as a presenter before working at ITV and then leaving to present Inside Sport at the BBC.
When Logan first started out as a broadcaster, she said she spent time proving “people wrong” who looked down on her being a woman presenting sport but said “it’s really satisfying” there is “more representation” today.
Logan also said the Lionesses winning last summer’s Uefa Women’s Euros was for many women “emotional” as it was about “purpose and about change and about possibility”.
She added: “It’s about young girls seeing women do extraordinary things and knowing they could do something extraordinary too.”
Logan also reflected on the fame she has had, saying: “There are times where you get dangerously close to being what I describe as being an asshole.”
She said she “came quite close” and said it was about having “good people around” to “pull you back” to reality.
Logan added: “You walk literally up red carpets and you’re being sent things for free people, people will open doors to restaurants that you previously didn’t think you’d get into and given tables and, you know, just for what presenting a bit of sport on the telly.”
Desert Island Discs airs on Sunday on BBC Sounds and BBC Radio 4, at 11.15am.