Peter Pan is the Royal Shakespeare Company's big hit at the Barbican Theatre. RICHARD BAKER flew in to talk to directors Trevor Nunn and John Caird about the formidable problems caused by an ambitious production which emphasises the serious side of J M. Barrie's classic. Barrie based it on the experiences he had as a child when his brother died at the age of 12; Peter Pan cannot grow up beyond the age of 12. Andrew Birkin , author of The Lost Boys, observes that the play was rewritten 36 times and the RSC have gone back to the original version . Bernard MacLaverty is a novelist who was born in Belfast and now lives on the island of Islay. Like Barrie's, much of his writing derives from his childhood, when at the age of 12 MacLaverty's father died. His short stories ' My Dear Palestrina ' and ' Phone Fun ' were adapted for television. His new book, Cal, deals movingly with the sectarian violence in Belfast.