Kassey (who is often mistaken for his twin Patrick) is a pyrotechnician, and a master of making fireworks. He is apparently better than his brother at making the fireworks. He makes them using a special, secret formula that he won't give to anyone. To tell him apart from his brother, look for the large yellow smiley face on his overalls. It's revealed that he has a crush on Muffy.
Him and his brother live in their water-tower like home near Cody, just south of Romana's mansion. The player can visit their home and are able to play a mini game against him or his brother if they are home. The Game consists of making triangular patterns. In the special edition, he or his brother will give you the "64 Memories" record if you beat them 10 times.
Befriending Kassey and his brother may influence your child to become an artist.