As stated in All Grown Up season 4, episode 12 Chuckie is exactly 13 months, 3 weeks, and 5 days older than Tommy.
Despite having contrasting personalities, Tommy considers Chuckie his absolute best friend and vice versa. They have been close since the start of the series. In addition, not only does Chuckie see Tommy as his best friend, he also sees him as a role model and when they were younger, a superhero. Although they are almost always on good terms, there have been instances in which Tommy or Chuckie are aggravated by each other`s actions. For instacne in TP+KF, Chuckie calls Tommy a sister stealer. In spite of it all, both love each other and their friendship stands to this day.
Kimi is Chuckie's step-sister. Chuckie is overprotective with Kimi a lot and if she does something he has to know about it but Kimi doesn't understand why he's so over-protective and she's so under-protective. Although when Chuckie is bad she manages to keep it a secret but Chuckie has to pay her back as seen in Petition This Chuckie had a secret instant and he claimed "I was baking waffles!" And finally close to the end they confronted each other bad by lashing out at each other in the episode and live in front of all the popular kids at school she told the instant to the whole school and they laughed then Chuckie said 2 quotes I remember "well she still sucks her thumb" and "she asked Santa for a cell phone 3 years in a row!" and Kimi admitted she did and yelled to the crowd as she cried "I wish I never started this dumb petition anyway!" which made Chuckie feel bad.
Chuckie has known Angelica since they were 2 and he knows she has the guts to do anything as he said "Angelica once stuck her head in the freezer for 2 hours just so she could get out of a math test." Chuckie and Angelica are pretty close friends despite her always teasing him and the others. Chuckie is the closest to her age (him and Susie). Angelica tried to help him when he liked one of her friends, and to make him popular and when everyone started liking the new fake Chuckie more than her, he felt bad and gave it all up for her. Angelica was also the only one of the group to know Chuckie's full name, not even his best friend.
Chuckie and Dil were never the closest of friends but they definitely are good friends. After Tommy and Chuckie got in a fight over Armadillo Dave comics ending Dil was the only one who understood Chuckie, even without talking to him. Dil pointed out to Tommy that "...we don't know what it's like to loose someone you love, Chuckie does, his mom."
Chuckie and Phil are very close but aren't seen hanging out by them selves often or interacting as much now their grown up. But the two are still close friends and get along even though they can sometimes disagree.
Chuckie and Lil aren't as close as they were when they were younger but the two are still pretty close. And in one episode Lil helps KImi reinvent Chuckie so that a girl he liked would like him back.They are also very good friends and always there for each other.
Chuckie and Susie aren't super close but are still good friends. Susie used to protect Chuckie from Angelica and for that her was grateful and when her Reptar cereal bars tasted horrible he didn't want to tell her because he wanted to protect her from the harsh truth.
Chuckie disliked Z at first because he and Kimi took and interest in each other and his brotherly instincts kicked in because he heard bad rumors about Z, circumstantial evidence and he dressed like a bad boy.
- He used to be right handed but it felt weird so he changed to left
- His favorite superhero is Armadillo Dave
- Even though Melinda died when he was a baby, he still remembers one particular day with her and still loves her a lot and the loss of her (despite his love for Kira) is why he was so devastated when Armadillo Dave was cancelled (as made obvious by Dil)
- Angelica taught him how to lie (and it came in handy)
- Angelica helped him get the attention of his crush (her friend)
- He and Tommy both suck at plant sitting