The kids live in a village with their families.
History[]
Scooby-Doo! World of Mystery[]
The three kids were with their parents when they were talking to the gang about a Specter haunting the Castle of the Knights and scaring people away, various kids around the village would go missing for days on end, before reappearing like nothing happened.
The kids climbing out of the costume.
In actuality, they were in disguise as the Specter via standing on each others shoulders and scaring away the adults. They had been trying to do that because they wanted to play alone in the castle with no adults watching them, they even setted up a decoy as a backup.
Eventually, they ended up getting stopped by Velma, who handed them a bag of chocolate causing them to exit out of the suit, and they were later reunited with their family members.