Please bear in mind, although both of their speech is odd for me because of their annunciation or lack of, Elvis really does seem to be competing for attention. Ocean is very very… feral, lol, and I can really imagine he doesn’t get the attention he deserves because she has to be front & center. A lot of Elvis’ behavior could simply be due to that, even his speech (especially if the other 3 members of his family cannot speak) He appears to be a really sweet & placid toddler too, so he could just have a naturally quieter personality! A new baby due in a couple of months isn’t going to do Elvis any favors, either.