Genevieve expressed confusion when Penny brought up the fact that she noticed something was amiss, though Penny wasn't sure if the confusion was real or feigned. Penny watched her thoughtfully, though, and what she said and did next convinced Penny that there definitely was something going on, despite the fact that Gen had thought for some reason that she wouldn't notice.
"I don't know that I would be considered as just 'anybody'," Penny chastised mildly, though she smiled to show her sister that she wasn't actually insulted. Perhaps no one else in the family would have noticed, even simply because they weren't paying attention, but such things didn't slip by Gen's twin.
Penny twined her arm around her sister's arm, laughing softly. "And none of your games, Genvi," she added. "Do tell me what's on your mind!"