The Heirs of Clan McDuck

Scrooge McDuck thought he'd lost everyone he cared about that fateful day Della was lost. Then, he finds the sole remaining egg of the quadruplets, who he takes in as his own. A couple of months after that, on his doorstep, he finds his ex, his former partner, and a pink-bowed bundle of joy who has his eyes.

Or, my Quadruplets AU combined with the Webby O'Gilt AU by neopuff, heavily inspired by NatureWitch21's 'A Different Tale'