Okay, I've seen some people do this in their books and though it would be fun to try :3
These are Headcanons that are technically canon bc I'm writing the story XD

--I was going to kill Cloudstream in the second chapter, but killed Cedartail instead. Of course she still died later..

--Cloudstream, Brightstorm and Flamewind grew up together. Brightstorm was always with their mother while the other two were pretending to be Warriors, but now is the most serious warrior of the three, albeit the only one with kits

--Cloudstream really wanted to be a mother

--Brightstorm and Cloudstream's parents were Snowytail and Rainstorm

--Riverpelt had a fleeting crush on Silverstar when they were apprentices

--Greyflower is Silverstar's daughter

--Briarpelt had had a crush on Flamewind since apprenticeship and Cloudstream knew the whole time

--Rogues killed Snowytail and Rainstorm died of greencough

--Bramblestrike was supposed to be Bramblespark and was supposed to be a girl, but when writing the chapter I said 'tom' multiple times and didn't want to change it so he's a guy now.

--I didn't think the allegiances through very well when beginning this book, so half of the clan's parents/mates are dead or unmentioned (meaning I have no idea what their lineage is XD)

--Thornpaw and Ashpaw are the kits of Brightstorm and Riverpelt, if you didn't catch that

--I have realized that some of the names I've used were cats in the actual books

--Silverstar's warrior name was Silverheart

--Goldberry is derived from a character in LOTR