Operation Cupid (tartali !¡ zhongchi)

Childe is called by the Tsaritsa after La Signora's funeral, he expects a lot of things: a new mission, some critique on the way he handles things or even retaliation for being less than focused on his job lately. What he received, however, was far beyond what he predicted: Rosalyne was raising a child that none of the Harbingers had ever heard of and, after her death, the cryo archon had reached the conclusion that Tartaglia was the most qualified one to take care of the little brat.

So there he was: back at his job in Liyue, with a child that is seemingly incapable of minding her own business and a still unresolved relationship with a certain consultant at Wangsheng Funeral Palor.

Or

The fanfic where a kid realizes that the great Rex Lapis and the 11th Fatui Harbinger are in love with each other before they do.