Basically we have 3 sets of molars that come in when you are 6,12,18+ years of age. That is IF everything goes correctly. If another tooth is in the way, the tooth will get stuck. Things can change throughout life and a wisdom tooth can erupt at later ages.
So to answer your question directly. No, your parent, grandma/pa didn't just grow a wisdom tooth. They have had it since they were late teens. It is very possible that the wisdom tooth is now erupting.
Now tell your ma or pa or grandma/pa to go see a dentist rather than using sdn for advice.