Their father played professional football but Alex Nelson is a huge prospect for the 200m (and 100m) and is helping to spur on younger sister Ashlee.
Campbell says on:
Alex Nelson, 20
"He's got a great start but has also worked on his weaknesses - particularly his final 30m. That is what you have to do - it's a slow process.
"Some athletes pull out great performances and don't know how to do it again so can't move on - Alex seems to know."
Ashlee Nelson, 18
"Ashlee has been doing brilliantly and is still maturing. Two years ago she lacked focus.
"She's told me she's focused now and knows what she wants. I think she realises she's been given a gift and wants to use it."
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