The frame and sentiment are both from this older American Crafts stamp set:
Speaking of square frames, Papertrey Ink is releasing a set this month called Square Prints that looks awesome for stamping backgrounds. Here's the release blog post with examples of the set in use: Introducing Square Prints, Think Big Favorites #24 and Everyday Photo Finishers. And some blog posts from Maile Belles, who designed the set: Introducing Square Prints, Square Prints Day Two, and Square Prints Day Three.
