As the rain begins to dissipate, Art chases the clouds to the edge of the city so he can keep his youth. He pulls his wife Dot along with him, but she isn’t able to keep up, and eventually lets go of his hand. He follows the rain to the end of the pier alone, but the rain stops anyway, restoring his age, and he looks back to see his wife looking totally defeated. As Brad Simonsen said, this moment is completely heart-breaking. In his race to the fountain of youth, Art essentially chooses that over more time with his wife, if only for a second.
Article source: https://www.cinemablend.com/news/2568787/disney-plus-us-again-producer-brad-simonsen-shares-break-your-heart-moment-solidified-the-film