SWIMMING a mile isn't something most of us could do easily. But for Maddison Brown it's an extraordinary achievement - she is just four years old. The amazing water baby, who has been swimming for less than a year, has completed 100 lengths in 100 minutes. Maddison is one of the youngest swimmers in the country to carry off the feat. She has been practising hard week in week out and swimming regularly for up to half a mile. Modestly, Maddison said she was 'quite proud' of her staggering achievement - and her favourite thing about swimming was having fun. Her thrilled mother Helen, of Blundeston, near Lowestoft, Suffolk, said Maddison was a natural in the water.    'From what I've been told this is quite unusual,' she said. 'It takes a lot both physically and mentally - a four-year-old can easily lose interest going up and down the pool 100 times.' She added: 'Maddison only learned to swim in July last year and then suddenly in a short amount of time she did quite a lot. 'She just really took to it as soon as she got in the water. 'It will be fantastic if she's keeps at it and continues to make progress.' Mrs Brown said her family were all keen swimmers and her brother had swum for the county when he was younger. Maddison is now determined to stay at the swimming club to improve her water skills and learn more strokes. 'Myself, my husband and Maddison's little sister Eleanor were all there to cheer her on,' said Helen. 'She's worked very hard and we are all exceptionally proud of her and this really is a lot for her to do.'   Swimming teacher Jane Tomlinson, who runs the Dolphin Swim Club based in Burgh Castle, Great Yarmouth, said 'Maddison is doing exceptionally well. 'She has naturally very good co-ordination and that helps - very few four-year-olds could have done this. 'There are three things you need to be a good swimmer: talent, a parent who is prepared to take you to lessons, and most importantly the child has to want to do it.'   Mrs Tomlinson is putting Maddison forward for the Amateur Swimming Association's national awards for improver of the year.        - Daily Mail