PJ Duncan is a guest star and a main character of Good Luck Charlie in Good Luck Jessie: NYC Christmas.
PJ is commonly portrayed as sweet, nice and sort of smart. As well as mature in his own ways and not really mean. However, he is at the same time, friendly, generous and kindhearted. He also showed many moments of creativity, resourcefulness, cunning and intelligence, implying he has a lack of interest and effort, rather than being genuinely slow-witted. He is also scared of turning into his dad when he grows up and realizes if he doesn't want a job as an exterminator he'll have to start paying attention in school.
As he got older, he became more intelligent, responsible and mature. PJ rarely gets annoyed or aggravated, although he will get angry if pushed to his limit. He is also hurt whenever he feels he has been wronged, especially by his family. He also prefers to solve his problems by talking them out, or by a subtly trickery (which often doesn't work). He can also be the voice of reason to others. PJ used to work at Kwikki Chikki. He has started his own band, called "PJ and the Vibe", with his best friend Emmett. PJ worries that someday he will end up looking like his dad and the band won't continue.
PJ has lived in the city of Denver, Colorado, since he was born. PJ has sat in the same chairs at the hospital in the delivery room three times, respectively, for the births of Teddy, Gabe, and Charlie (Charlie is 1). PJ graduated high school, but, we did not learn what college he’s going to be attending (Name That Baby). He strives to go to college, although he drops out in All Fall Down to go to culinary school. Overall, he is a compassionate, fun loving guy with a good heart. PJ did go to a college from his old job, Kwikki Chikki (Kwikki Chikki University). He got into a college, but he later dropped out. He also is bad with cars. (Special Delivery)
One of PJ's more defining traits is his ability to get along with near about anybody, from little children, to tweens, to teens, to the middle aged, to the elderly, he can get along and befriend them with ease. This is mostly due to his conflicting muture/childish personallity, respectful nature and natural kindness and friendliness.
In Baby Steps, PJ moves in with Emmett.
PJ is shown to have some musical talent, and he has a band called PJ and the Vibe with Emmett. He is also an excellent chef, able to make nearly any dish without really trying, and dropped out of college, so he could go to culinary school. He's also very good at reconciling others, and is shown to be quite good at talking his way out of situations. He is somewhat a good babysitter.