WP

I noticed this working both ways - I've several times shrunk pets who took damage only to unshrink them later and find that they passively regenerated health while shrunk. And last night I shrunk a drake with very low health who was under the effect of a high-level poison and it died while shrunk. The effect of that was it looked fine but when I tried to unshrink it, no pet appeared but it still took up 2 of my pet slots until the server reboot zeroed it again.

You should never shrink a pet that is poisoned. Shrinking doesn't actually "freeze" them so they can die, or regen health, while in shrunken form.