{This is not a missing ask. I just accidentally deleted it because my inbox was showing it twice when only one copy existed. Or in other words, the mun is an idiot, and I apologize. D:}

Hm. First off, determine whether or not your pichu is incapable of evolving or if he simply refuses to evolve. I suspect, given the fact that the two of you have been together for a long time, the latter is the case here. If that’s so, this may be a sign of the opposite: your pichu cares about you so deeply he may be afraid that evolving will change his relationship with you or his ability to help you. Evolution brings about a shift in personality, after all, so if you’ve reached a deep bond with him as a pichu, that may change once he undergoes the evolutionary process. I must say, though, that while wild pikachu can be ornery, tamed ones are very quick to bond with humans. His fear is valid, but he shouldn’t worry as much.

If this is the case, it’s important to reassure him that you will still be his friend and still try your hardest to maintain your friendship after he changes form. Also bring up the fact that pikachu are a little more expressive than pichu (they have, for example, more digits with which to sign, as well as a full tail and ears to add to their signals), so his evolution shouldn’t hinder his ability to communicate with you. If anything, it should help you, as pikachu with close bonds with their trainers can also adopt their emotional reactions, which may aid him in his attempts in communicating your thoughts to others.

Of course, this isn’t the only reason why he may be resisting evolution. The other reason may be a personal one: he may simply prefer to be a pichu because he feels more comfortable that way. If that’s the case, then let him know you support him wholeheartedly and that if he ever changes his mind, you will still stand by him. This will allow him to be a bit more comfortable and feel more in control of who he is, which will only help his emotional health.

If, however, he’s incapable of evolving, I would open up a conversation with him to at least eliminate the possibility that something about your relationship is bothering him. If he’s happy, then I would take him to Nurse Joy for a checkup. There are a few very rare conditions that prevent pichu from evolving, even if their evolutionary requirements are met. Some, such as spike-ear syndrome or pikachu-color syndrome (both of which are marked by self-explanatory physical traits) are actually genetic mutations that result in a pichu being locked in a single form for different reasons. Scientists aren’t entirely sure why spike-ear syndrome are incapable of evolving, but those with pikachu-color syndrome are born with a blend of pikachu and pichu genetics. In other words, their bodies think they’re both pikachu and pichu at the same time and blocks evolution because they can’t tell on a genetic level what evolutionary requirements are necessary to evolve. Thus, all of the requirements for the pichu line cancel each other out and render the resulting pichu stagnant.

In other words, @terra-bunny-collector-edition, don’t worry too much! If you’ve treated your pokémon with love and care, then even if happiness with their trainer is an evolutionary requirement for them, the outright refusal to evolve (rather than the inability to do so) is only a sign that they’re comfortable with you and their forms. And if it’s a genetic condition instead, it’s very likely not an issue that will harm your pichu in the long run.