Design the number fifteen ('15') with a bold outline, including the '1' and '5'. Inside the '5', which has a rounded top and bottom, place up to 5 small, proportional toy images such as toy airplanes, blocks, or stuffed animals. Important: Ensure that the number '15' and all toy images inside the '5' have no internal color whatsoever—only black outlines. There should be no shading, filling, or any color other than the outlines. The '1' should be left plain or with minimal detail. Ensure that all elements are contained within the rounded parts of the '5', with no lines or divisions inside.