Caterpillar + eggs?

[Keg]

Have got a fair few of these on my house. Whats it all about? The caterpillar initially looked as if it was in the web with the eggs (?) but has since moved around, though it always stays by them.

[triops]

The caterpillar is of Pieris brassicae, the Large White butterfly. Some weeks ago a small parasitic wasp, Apanteles glomeratus, injected some of her eggs into the caterpillar, and now the parasite larvae from those eggs are full grown they have burrowed out of the caterpillar and spun themselves silk cocoons. All that remains of the caterpillar is mostly skin.

[Keg]

Many thanks.