4th Gen My Geodude is level 34. Why hasn't it evolved?

[7hiiiiiii]

My son is playing Pokemon diamond and his Geodude hasn't evolved into Graveller yet. He really wants a Golem, which i know you have to trade to get. I looked it up and it says it's supposed to evolve at level 25. What's up with that?

 

[CodeHelmet]

Hmm does it happen to be holding anything like an Everstone perhaps? Also does he happen to do anything during the "Evolution" process like pressing B to halt it? Also it learns Stone Edge at level 39 so maybe that's what he's working towards? Can't really think of anything else that would prevent the Pokémon from evolving after it gains a level.

 

[7hiiiiiii]

I checked and he doesn't have an everstone. He doesn't normally press anything during evolutions and doesn't recall geodude ever about to evolve. I guess we'll wait on level 39. Otherwise i guess he will just have to catch a Graveller