A 74-year-old tortoise who has been in the same family for almost 50 years has been stolen. Shellie, a favourite with neighbourhood children and her owner’s grandchildren, was nabbed from Diana French’s garden in Rough Common, near Canterbury, on Thursday morning. Mrs French, who has taken care of the Mediterranean tortoise for decades, says it’s hard to believe she’s gone. “I’ve looked after this lovely tortoise of 49 years. She was 25 when we got her so she’s now 74,” she says. “We had the tortoise when our son was three because he was mad about tortoises – he’s now 52. “It’s difficult to be…