Photographer Seth Casteel’s underwater photographs have captivated an international audience, leading to bestselling photo books Underwater Dogs and Underwater Puppies. Now, after what Seth says are among the most joyful shoots of his career, Casteel has found a new way to capture images of our youngest humans at their most playful and pure: underwater.

Underwater Babies is Casteel’s latest book with more than 70 previously unpublished photographs. Underwater Babies reveals adorable babies as they explore the underwater world, chubby-cheeked, curious, mischievous, and joyous, all in Casteel’s signature style.

Seth was kind enough to reach out and share some photos from his latest book which you can see below.