The sunny beaches of Edisto Island, South Carolina is full of lively sea critters, but none more spectacular than the horseshoe crab. It was during this time visiting Edisto Island that Jeanne Prebble learned about the horseshoe crab's contributions to the safety of medical vaccines. Unbeknownst to most, the blue blood of horseshoe crabs has the remarkable ability to make vaccinations safe for human use. In Hank the Tank by Jeanne Prebble, Hank, a young horseshoe crab, spends his days playing with his friends along the bottom of the ocean. But as Hank and his friends and family travel to the shores of Edisto Island on spawning day, Hank becomes stuck in the sand while playing hide and seek with his friends. On his back and unable to turn over, Hank meets an unlikely friend who saves his life. Little does he know that in the coming future, he will have the chance to save her life and those of countless others too. Once a retired registered nurse, Prebble came out of retirement to work at a local COVID-19 clinic in Grand Rapids, Michigan. Prebble believed in the hope of vaccinations to eliminate COVID-19, and it was during this time that she was fascinated by how horseshoe crabs contributed to making all vaccines safe. Hank the Tank was written during the COVID-19 pandemic in 2021, and Prebble would like to thank all the children and parents who rolled up their sleeves and were vaccinated.