Quick edit from my TikTok! It's from a fanfic called Declared Flase Start by WanderingDonut on Ao3 and its thr only thing getting me through right now, so I thought I'd show the author some love.

This fic follows Regulus Black after Sirius had run away, leaving him alone in the oppressive pressure of Walburga. She pushes him heavily into swimming and as a nationally ranking competitor after Sirius left before his own Olympic Trials. However, after he had a panic attack mid competition, Sirius reaches back out to him. Slowly, Regulus escapes the internal prison of his mother.