I might bet that the calla was not actually dead... Maybe just the tops... I hope u didn't toss it. They are about as tough as they come for easy plants. the tops may go to mush in an early freeze, or late one, or they may shrivel and become crunchy in when totally neglected in a drought, but they always come back.
I have tons of em that I've dug from other peoples yards - they wanted em gone- that were tossed to the side, forgotten about, whatever ....now I have em growing in some strange places, like in the bed of my ol' pick up .