One of the six political books for kids you should definitely read according to Zoe Williams in the Guardian, November 2018! Roy and Silo are just like the other penguin couples at the zoo - they bow to each other, walk together and swim together. But Roy and Silo are a little bit different - theyre both boys. Then, one day, when Mr Gramzay the zookeeper finds them trying to hatch a stone, he realises that it may be time for Roy and Silo to become parents for real.