In a document about 边缘性人格障碍 (biānyuán xìng réngé zhàng'ài) = "Borderline Personality Disorder", we have the following sentence:
Bìngzhēng zài chéngnián zǎoqí jí yǐ xiǎnlù, dàn suí niánlíng zēngzhǎng qū yú huǎnhé huò wěndìng.
I translate this to:
Symptoms become visible at early adulthood, but with age they have an increasing tendency to alleviate or stabilize.
I think it's a reasonably accurate translation. (Google Translate gives a translation that's much the same: "Symptoms are revealed early in adulthood, but tend to ease or stabilize with age.")
What I'm confused about is the use of
- 即 (jí), which means something like "namely" (also mentioned in What does 即 mean in this sentence?), but I don't think that makes sense here, and
- 已 (yǐ), which means something like "already".
Neither of these makes sense to me in this context.
Question: What do 即 and 已 do in the sentence 病征在成年早期即已显露?
There's a few examples of 即已 used together on YouDao, but I don't see how they help.