The world has fallen in love with the way Janice Clark reads to her grandson.

As she tried to read The Wonky Donkey to her baby grandson this summer, Janice Clark of Queensland, Australia burst into uproarious fits of laughter.

Her daughter captured the moment on video and shared it with her sewing group on Facebook, where it went viral. Now, the book, which was published in New Zealand in 2009 and had largely been forgotten, is an international bestseller.

Clark is originally from a “wee village” in North Ayrshire, Scotland, according to her Facebook page. In 1973, she and her husband emigrated to Australia, where they raised two daughters.

She’s been overwhelmed by her unexpected fame, she recently told Publishers Weekly. Last week, The Wonky Donkey’s publisher flew her and her family to New York City, where she read it to a rapt audience of more than 100 children, teachers, and parents at Barnes & Noble.