Near the end Lois reacts happily to being regarded as a "mom in her 40s". Earlier Meg tried to make her seem older by making her a "Happy 50th Birthday" banner, which both imply that Lois is not yet 50. But when Meg asks her who was President when she was born, Lois starts to say "Dwight D. Eisenhower", but if that was true she'd be at least 60.