Maturity is not required: it would be irrational to expect proper behavior from a child in this situation.

Legion themselves is doing better than many of those on the island, even if they aren't perfectly well: flowers spill from their chesthole but they feel no pain, only elevated temperature and some confusion. Additionally, those flowers seem to be... wilting? They're looking decidedly less vibrant and healthy than Kaworu's, at least. Occasionally, a crimson petal falls.

They see their young ally, and decide to approach.

"Kaworu."