Like Christine and Anthony Clark, dealing with children's petty squabbles, tantrums and bad sleeping patterns is a daily battle familiar to most young parents. But Mr and Mrs Clark are not young parents. They are in their 60s - an age where most of their friends are enjoying their retirement, and their 'boys' are actually fully grown men, each with families of their own. Brothers Michael,42, and Matthew Clark, 39, from Hull, have been diagnosed with leukodystrophy — a rare genetic disorder that causes a progressive loss of speech and movement. An extraordinary documentary tells the story of Tony and Christine Clark and their two sons Matthew (39) and Michael (42) as they live and cope with a condition which has made them regress to childhood
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Brothers Michael, 42, and Matthew Clark, 39, from Hull, have been diagnosed with leukodystrophy
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The condition has turned them into  young boys, trapped in adult bodies
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The Curious Case of The Clark Brothers, tonight at 9pm on Channel 4
She said: 'They can be very affectionate, particularly with one another – they'll often put their arms around one another, and @placeholder will say, 'He's my little brother'.