One of Torchwood’s ongoing projects was to tag as many Weevils as they could to track and identify them. Whenever time could be spared, they’d round up a bunch, check their health, catalogue them, inject trackers and return them to the sewers.
Weevils were unpredictable; the team could never be sure whether they would attack or try to escape when they were approached, but this was new.
Coming across a group of three adults, instead of attacking, the Weevils had approached, two of them helping the third, which was injured.
Maybe their project was having a positive effect after all.