For a parent, breaking the news to your only child that there's a baby on the way can be a nerve-racking - but touching - moment. And for one family who decided to film the precious moment, it also became a hilarious home video clip. Mum Megan Williams revealed that her two-year-old daughter Kathryn is constantly asking for a little brother or sister. Breaking the news: Kathryn, two, sits on her dad's lap to be told she is going to be a big sister . So she decided to sit Kathryn in her father's lap, and film her reaction as they told her the news using a special book titled 'The Big Sister's Book of Waiting'. 'Do you know why we've got you this book?' her dad asks. 'Because you're going to be a big sister!' For Kathryn it was all too much. As she digests the wonderful news, she struggles to keep the excitement in - in one sense at least. Helping hand: Her parents showed her a book called 'The Big Sister's Book of Waiting' Little surprise: But her reaction wasn't quite what her parents were expecting . She leans over to her father and whispers, 'I farted' - leaving her parents in stitches . The clip, uploaded to Someecards' YouTube page, has had almost 500,000 views since it was published on March 19. In stitches: She leaned over to her father and whispered, 'I farted' - sparking a fit of giggles .
Two-year-old Kathryn had always wanted a baby brother or sister . So mother Megan Williams filmed as her dad sat her down with a special book titled 'The Big Sister's Book of Waiting'
Her reaction wasn't quite what her parents were expecting, however .