I would love an ID on this caterpillar AND if it has come to its death due to being implanted by parasitic wasp eggs that are now larvae? It was really interesting, because then the mass was eaten by a European wasp.
It was all quite interesting to watch.
For clarity, I have provided image of both the 'dying/dead/ caterpillar and one of the live caterpillars found around it that I believe to be the same species?
Agree with donhe's suggestion - Cabbage White butterfly caterpillar - and yes, the parasitoid wasp larvae lead to the caterpillar's eventual demise. For a bit of info on these beneficial parasitoids see: https://cesaraustralia.com/pestfacts/parasitoids-cotesia-apanteles/