Corrected entry: After Picard, Guinan, Ro, and Keiko all beam back to the ship and have been transformed into children, their clothing hangs loosely on all four. Later, Dr. Crusher even states "But as far as we can tell, only their bodies were changed". Presumably they replicate a change of clothes that fit before the next scene. However, no one on the medical team addresses the fact that the now pre-pubescent Captain Picard has an adult-sized parthenogenetic implant (fake heart) that was mentioned in many previous episodes.
Corrected entry: A transporter accident transforms Picard, Ro Laren, Guinan and Keiko O'Brien into small children who appear to be about 12 years old. Picard is 30-40 years older than Ro and Keiko. Guinan is over 500 years old. Why are they all returned to the same age?
Correction: Simple - their bodies have all been 'reset', as it were, to the same stage in their lives - apparently just before the onset of puberty. Therefore, they all appear to be the same age.
Correction: There is not enough information on the artificial heart itself to say with any certainty that it would have any adverse affects on a person were their body size to shrink. Since we don't know if it definitely would have any negative effects, we can't say it is a plot hole that it doesn't.
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