Mellie doesn't respond to any of the stimuli around her - not Sirius' fingers and talking, not the green man and his scanner, not the baby in her arms who's gone silent with fear at the strange silvery creatures. She neither blinks nor flinches, but restates the green man's words.

"Whatever you’re doing to my suit, you need to cease doing it immediately. To stop them, I need it to be functional - the equipment inside it is delicate."

And by then the translation spell has taken such hold that Mellie's talents are no longer necessary. She blinks and looks around, looks at the kid in her arms, at the green man in front of her and Hottie McLonghair right next to her (ooh, he smells a little wild) and, in a daze, asks "did I fall asleep?"

Because that's what she needs when aliens are invading: narcolepsy.