Parasitic wasp larvae hatching from inside the living caterpillar host. The
female wasp will oviposit into the host’s body. The larvae will feed
inside the host until they are ready to pupate. Quite often the host is
dead by that point but if not, then the parasitoid will often eat its
way out of the host.

Royal jelly is a honey bee secretion that is used a nutrition for
larvae and queen bees. When worker bees decide to make a new queen
because the old one is either dying or dead, they choose several larvae
and feed them royal jelly in specially constructed queen cells. This
triggers the larvae to develop with queen morphology, including fully
developed ovaries needed to lay eggs.