“How do you think of so many rooms to put in the treehouses?” “What is your favourite book – and who is your favourite character?” “What food do you eat the most?” “What’s going to happen next?” In Guardian Australia’s new series, Ask A Children’s Author, writers are offering to take their young readers’ questions – about the book, about the characters, about anything at all, really. First up is Andy Griffiths – the author of the Bad Book series, the Bum series and, of course, the number one bestselling 13-Storey Treehouse series. If your child is a fan with a question for him, please post it in the comments along with their first name, age and city. Or, if you’re looking for a lockdown activity, film them asking the question and email the video to australia.culture@theguardian.com with the subject heading “Andy Griffiths”. The question might make it into the one we publish with all his answers – so long as you send it before Monday 4 May …