Life With Derek Wiki
Casey McDonald
File: Hurray_hurrah.jpg300px
General Information
Gender: Female
Age: 15 (Season 1 and Season 2)
16 (Season 3)
17 (Season 4)
18 (Vacation with Derek)
Hair Color: Brown
Eye Color: Blue
Birthday: 1990
Occupation(s): Student
Family & Friends
Family: Nora McDonald (mom)

Lizzie McDonald (sister)

Dennis McDonald (father)

George Venturi (step-father)

Derek Venturi (step-brother)

Edwin Venturi Venturi (step-brother)

Marti Venturi (step-sister)

Simon McDonald-Venturi (half-brother)

Victoria (cousin)

Relationships: Sam Richards (Ex-boyfriend)

Truman French (Ex-boyfriend) Max Miller(Ex-boyfriend) Jesse (Boyfriend)

Friends: Emily Davis
Pet(s): None
Enemies: Victoria 'Vicky'
Other Information
Interests: Dancing, Plays, Cheerleading, Literature, Boys, & Bands
School: Queens University
Series Information
First appearance: The Room
Last appearance: Vacation With Derek
Portrayer: Ashley Leggat

Casey McDonald (Ashley Leggat) is the oldest of the McDonald kids and the second oldest in the Venturi-McDonald family. She spends most of her days at school worrying about her annoying older step-brother Derek, and stressing about her grades.

Character Description[]

Casey is a smart and well-mannered girl. Once her mother gets remarried, she is forced to move schools and homes to live with her new step-family which would've been easier without Derek. Casey has a Type A personality meaning she is very particular about academics and is quite a perfectionist, a bit of a drama queen and likes to have things her own way (although what she isn't able to do is relax and is always worrying about something). Although Casey is not always nice and well-mannered, Casey can get really mean or selfish when her step-brother Derek annoys her. In Vacation With Derek, Casey's straight A's get her into Queens University. She plans to double major in English and Economics but drops it to follow her dream of dancing.


Casey has a quite a few hobbies, such as dance. Casey loves to dance, especially to jazz and hip-hop. In fact, as a kid, she attended many dance competitions where she dressed in various animal costumes and won many trophies (and it is shown that she keeps all these memories in an album). She also becomes a cheerleader and is fairly good at it, too.

Relationships with others[]


Casey and Derek are complete opposites. They argue, scream at each other and get on each other's nerves. They often clash with each other being that they are the exact opposites and the oldest children of the McDonald-Venturi's. They go to the same high school and try to ignore each other in the halls. Derek likes everything to be done by his rules and Casey does not, which is the cause for a lot of their arguments. Although it may seem like they hate each other, they really do not, and actually notice that they need each other and do love each other, no matter how much they argue with each other. An example of this is shown in the episode "Prank Wars" when Derek is going to get expelled, and Casey is shown as kind and doing her best to help.

While the show progresses, it's shown that they are slowly getting along with each other better than they did in the earlier days of their parents' marriage. Though they still bicker a bit, they tend to work things out a lot easier after all the things they have been through together.

One thing about Derek is that he won't let anyone else tease or pick on Casey because of his firm belief that only he can do that to her.

Derek can at times be a protective big brother to Casey, but also her true friend. It is sensible that Derek and Casey got each other's influences by the natures and personality, which Derek has become more sensitive, showing compassionate emotion for Casey as well as less conniving and less immature. As for Casey, she learned how to be cool, and likes to often prank and tease Derek while becoming a bit sneakier (which wasn't her natural self), and sometimes becomes insensitive and also a bit rebellious.

Emily Davis[]

Emily is Casey's best friend. They met on the first day of school and Casey got advice, help and tips from her concerning general conflicts and school issues. She is also the McDonald-Venturi clan's next door neighbor. Emily also helps Casey with her popularity.

Nora McDonald-Venturi[]

Nora is Casey's mom. She helps Casey out when she's needed. Only sometimes do they have issues with each other.

George Venturi[]

George is Casey's step-dad (as well as a corporate lawyer). They don't do many activities with each other. Sometimes, Casey has to help George when he forgot something when it comes to things around the house and with Nora. In the episode 'Take Your Stepkid To Work Day' they need to work together, which doesn't go very well. (In the Season 1 episode The Fall, Casey tells Corey Plunkett about her lawyer being her stepdad, and he realizes what she meant when Derek tells him to cut Casey some slack, as she is Derek's stepsister.)

Lizzie McDonald[]

Lizzie is Casey's sister. They always on the same side when it comes to debates or conflicts within the two families and help each other out with their problems. It is demonstrated that they care for each other and love each other. Casey is also very protective of Lizzie.

Edwin Venturi[]

Edwin is Casey's step brother and they don't do many activities with each other, likely due to the gender difference and age gap, though they do talk sometimes. Nevertheless, she is also protective of him.

Marti Venturi[]

Marti is Casey's younger stepsister. She spends time with Casey and talks to her a lot despite the two being rather different people. Casey is also extremely over- protective of Marti and they appear to have a Good relationship. Same as Derek, she has a soft spot for Marti, which she loves and sees her as her little sister (i.e. In the "Futuritis", at the last part of the episode, Marti said to Derek, "Because my big sister told me to", and Casey thought it was herself.)

Paul Greebie[]

Paul is Casey's high school guidance counselor. Although it seems Casey often goes his office to get advice, it turns out that in reality, he only gives suggestions, and also lets Casey figure things out on her own. Casey often needs his help, and finds it nice that he's around when she does.

Love Interests[]

Max Miller[]

Casey dated Max, the school's football team quarterback. Before Casey, he was dating Amy, the head cheerleader. After their breakup, he asked Casey out. They started dating in the episode "Misadventures in Babysitting". They were a normal couple after Casey gets Max to be more polite. Their relationship lasted a good while and his behavior continually improved. In the episode" Allergy Season", Casey believes she is allergic to Max's jacket, making her think there is something wrong with their relationship, so after the championship game, she breaks up with Max.

Truman French[]

Truman is a new kid in Casey's school. He first appears in the episode "6 1/2" where he rates girls out of ten and only gives Casey a 6 1/2. Casey starts having dreams of him, but when Truman says she likes him but she denies it until the episode "No more Games" where they agree to date. Though in the episode "Truman's last chance" Casey and Truman go to a party together. But when Vicki ( Casey's cousin) kisses Truman, Casey thinks he kissed Vicki and breaks up with him.But in the seccond last episode "Suprise" they get back together during prom  beacuse he apologized and explained his reasoning.


Sam is Derek's best friend and Casey develops a crush on him in the episode "The Fall." Derek accuses her of her crush when she falls when in front of him twice. Later, Sam is revealed to have feelings for Casey as well and they

Casey and Sam kissing

start to date but Derek wants to break them apart ,but continues to fail. In the episode "Middle Manic," Casey and Sam frequently break up and get back together again. By the end of the episode they break up for good.


To visit the Casey McDonald Gallery click here