Sam Caldwell has illustrated When a Moose Has a Mustache, an oversized board book with gatefolds published by Gibbs Smith (September 2026). A delightfully silly forest adventure, the book follows a cast of anthropomorphised animals, each sporting a different mustache that behaves in its own wonderfully absurd way. A moose with a hiking stick, a toad with a fishing pole, a coyote catching fireflies and a mouse roasting marshmallows over a campfire round out a cast that shows Sam's playful, character-driven illustration at its best.