Climb up to the party. This storybook treehouse scene by The Pattern Peacock is packed with the kind of hideaway-adventure details kids love to pore over, and it sets the mood for a whole day of make-believe. Inside: "Happy Birthday — Have a happy day full of fun!" with space to write your own.

Folded to A2 (4.25" x 5.5") and paired with its envelope, it's a charmer for imaginative kids and backyard-fort dreamers alike. The treehouse detail rewards a second look — exactly why this one gets tacked up on the bedroom wall.