Laura Trott has revealed that she promised to buy her sister Emma a car if she won two golds at the Games.
Giggling, Trott told BBC Breakfast: "I hope she's got a budget, there'll be no Ferraris, I'm telling you."
Talking about the future as she appeared on the sofa with six-time Olympic champion Sir Chris Hoy, Trott joked: "I could beat him, eh?"
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