Mrs. Piggly only appeared once in The Next Wave, in which game she was inexplicably found floating in space between Neptune and Uranus. A warning sign was placed nearby, which the Hero noticed just in time not to crash into her.
Mrs. Piggly is one of the only assets not be rerendered in a higher resolution in The Next Wave, presumably because InterAction studios lost her old model.
Thanks to this, Mrs. Piggly is much smaller in the remastered version than she was in the original version.
Just like The Next Wave referenced Piggly, her own series also referenced Chicken Invaders. In her most recent game, a Chicken of the regular breed bearing a shocked expression can be found in multiple secret areas along her journey. When it reappears in the final level, she tells him "Shoo! Get your own game!".