A/N: Written for the:
The Sinnoh League Challenge - general version, Route 201 part 3 - write a farewell and include the starter you picked (Turtwig)
Diversity Writing Challenge, a82 - write about losing something
Never's not Forever
Her Turtwig vows to never change when they find the Everstone.
It's the perfect thing. She wants to zip around and becoming a Grotle will slow her down. It's the perfect thing because they're fairly close to Sangem Town and so she doesn't have to worry about some trainer trying to clean-sweep her with an Infernape (not that it hasn't happened before, and while it is tricky to catch those devilishly quick monkeys with a Grass Knot, it wasn't impossible by any means).
They can battle the way they always have with the Everstone. They can play the way they always have with the Everstone.
Humans grow slowly. Pokemon grow slowly too, if they don't evolve. They'll grow together. They'll play together, battle together, get stronger together.
They don't think they might lose the Everstone that stalls it all. They don't think that, in the countless battles they fight, they can have an opponent who can use Thief or Covet or Trick or Switcharoo… or even Knock-off. Embargo might be a problem, too. Or it might not.
It's Thief, in the end. A Monferno who shouldn't have been too much trouble after the Infernapes they've seen in their career… except it can use Thief and it does use Thief and, suddenly, the Everstone is gone.
And Turtwig is evolving.
Grotle isn't small and fast. They can try. They're a damn sight faster than most other Grotle out there - but it's not the same. It won't be the same. Grotle's changed and she'll have to deal with those changes.
Gardenia will have to grow up a little more and deal with that, too. Because they don't live in a world where they can stay young forever.
Post A/N: In game-theory, Embargo sealing the Everstone will not cause the pokemon to evolve, since pokemon don't evolve in the middle of a match, but the anime does have a habit of having in-match evolutions which means Embargo might be effective in sealing the Everstone and causing an evolution if the pokemon is ready to evolve (unless they pull a Piplup, but not everyone can use Bide on themselves…)