OK, so I lied. This morning, it was still fairly dark when I looked into the maternity suite and saw the two aliens. At that time I assumed it was the grungy yellow one Fric took up yesterday and the purple one I saw her heaving up the stairs this morning When it got lighter and I checked the box again looked again, I saw that there were actually two purple aliens, both tucked in a corner as if watching over the pups.
So, sometime during the night she removed the yellow alien–whom I have yet to find–and replaced it with the first purple one, perhaps after deciding that the porcupine would have overwhelmed the decor. Feeling the room was lacking with only one oject d’art but perferring symmetry, she replaced the yellow alien with another purple one. And in answer to someone’s question re: whether she was treating these like pups like females who lose a litter or have a false pregnancy sometimes do, she’s not. She does not position them with her pups or relate to them in any way once they’re in the box. She put them in the corner of the box, side by side and away from her pups and where she nurses them. Now I wonder where she put the yellow one…