I thought in universe it's still less than 1 year from chapter 1 to now, so whatever age Vermouth drank (before or after studied disguise with Conan's mom) and de-aged to it couldn't have been THAT long to notice visible aging (say 20+ years). So it's even less likely she took it multiple times.Surely this has something to do with Vermouth staying the same age all these years, no? It's not that she ages then takes a drug to be young again, she simply stays the same age, at least visibly.
... so the parents meeting is cancelled until next week, because the guy is concerned about Maria-chan.Calling it now, the kid who fell over the tulips used the underlay sheet to ignite the tulips on fire like a magnifying glass.
More like he thinks he'll get in trouble if they find out he killed a tulip, so he decided to use the ghost story to kill more tulips to make it seem like was innocent.... so the parents meeting is cancelled until next week, because the guy is concerned about Maria-chan.