This idea was given to me by WhenTheStarlightShines, and thank you for that! I liked the idea, so here we go!
Just like normal, Hollyleaf goes into the tunnels at the end of Sunrise, meeting Fallen Leaves and falling (heh) in love with him. Hollyleaf watches over ThunderClan, supplying them with herbs and prey whenever she can. Fallen Leaves notices that although she is happy with him, she misses her Clan more and allows her to go with the promise that he'll see her again. Hollyleaf appears to the Clans again, Lionblaze and Jayfeather being very happy to see her. Leafpool rushes over to her, crying tears of joy upon seeing her daughter alive, but Hollyleaf just feels awkward toward her and Squirrelflight still. Hollyleaf trains ThunderClan how to fight in the tunnels and getting rid of WindClan with the help of Fallen Leaves. Crowfeather even says he's pleased she's still alive; Sol gets banished and ThunderClan goes home.
In the Great Battle, Hollyleaf still saves Ivypool, but it's Ivypool that kills Hawkfrost because it makes for a better character arc ERINS! Hollyleaf doesn't die, and gets to see Fallen Leaves finally go to StarClan with his mother. But Hollyleaf has a secret: she's expecting kits. Fallen Leaves' kits.
The kits are born, being weirdly faded, but entirely there: a ginger and white she-kit with green eyes who looks exactly like her father, and a dark gray and white she-kit with blue-green eyes. Hollyleaf names them Fallingkit and Minnowkit. The kits seem to have strange abilities: Fallingkit swears she can see shapes moving that aren't there, and Minnowkit can see auras around cats, sort of like their emotions. It's because of Fallingkit's visions of the future that ThunderClan is able to get out of camp just in time for the flooding. When the manga (in Bramblestar's Storm) takes place, Minnowpaw thinks it's strange that she can see tiny golden auras around Squirrelflight's belly, and then realize it's because she's expecting kits. Minnowpaw and Fallingpaw don't tell Squirrelflight that they know two of her kits won't make it, but that the other two have great destinies.
Sure enough, Alderheart becomes the medicine cat, and Sparkpelt becomes Sparkstar after Squirrelflight and Bramblestar sacrifice their lives fighting the new Kin lead by Sleekwhisker and Raven. Sparkstar names Ivypool her deputy and Ivypool has kits because she's just not mother material. Tigerheart never becomes leader, and Tawnypelt does, naming Snowbird as her deputy. Hawkwing dies (because I hate him), leaving Violetshine to take his place as SkyClan's deputy. When Squirrelflight and Bramblestar die, Hollyleaf says that they were the best parents any cat could have asked for, even if they weren't her biological ones. Fallenpaw and Minnowpaw finally become Fallenpool and Minnowflight after Hollyleaf's two mothers.
A terrible outbreak of greencough takes over the Clans and Fallingpool warns her mother that Leafpool won't survive, leaving Hollyleaf to tell Leafpool that she was glad she got to know her mother better. The original Three are all there for Leafpool, and they all forgive her, leaving Leafpool to thank them before dying and leaving all five Clans to grieve because of the impact the medicine cat had on everything. Even Crowfeather says he doesn't regret loving her because it led him to him having pride for all of his kits. Hollyleaf takes one final stand, protecting Cinderheart and her kits (in a reflection of Leafpool not being able to save Cinderpelt because Warriors is about things like that) from the very last of the vengeful Kin in Sleekwhisker. Hollyleaf manages to kill Sleekwhisker, but dies due to her wounds, protecting her best friend and Fallen Leaves takes her to StarClan where they watch over their beloved kits.
QOTD: How many times did I say happy or leaving? Okay, serious question, though. Any stories you guys like? Or... I could talk about LGBTQ+ AUs like Draikinator's videos(check them out, btw, they're great. YouTube.)? Would you guys want to know what pairings are my favourite? Anyway, I'll stop rambling.
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