Ariel Winter is starring in the upcoming horror film Don't Log Off about a high schooler whose friends celebrate her birthday on Zoom and she goes missing. The role is a departure from studious Alex Dunphy on Modern Family, who often fights with her older sister Haley who is very different from her.

The siblings are known for their funny banter as they often joke around at each other's expense. While the Modern Family characters do appreciate each other more as they get older, throughout much of the sitcom, Haley and Alex say some comedic quotes that are unforgettable.

"At least look up the difference between astrology and astronomy."

Alex and Haley both like Arvin in the season 8 episode "Written In The Stars"

Haley talking to Arvin on Modern Family

Alex and Haley's terrible Modern Family actions can never be forgotten, and Alex has a tough time when her prof, Arvin Fennerman, likes Haley. Alex has been nervous to share her feelings with him, and she takes out her anger on her older sister by suggesting that she can't tell the difference between these two scientific subjects.

Haley and Alex making fun of each other is a familiar dynamic, and while it can be a bit harsh, in this moment it's played for laughs. Alex doesn't want to talk about her feelings or confront Haley, which creates resentment between the two of them that takes a while to clear up.

"A movie theater is a place where people go on dates."

Haley is upset that Alex has explained what a library is

Haley and Alex talking in Modern Family

When Phil mentions a library and movie theater while chatting with his daughters, Alex defines a library for her sister, and Haley gets upset and suggests that Alex doesn't have a love life. It's funny that Haley's interpretation of a theater has nothing to do with seeing a new film or enjoying some popcorn and candy.

Haley's young adult life revolves around dates, and she often cracks jokes when talking to Alex because she's so insecure about Alex's intelligence. It takes Alex a while to realize this and once she does, the two are able to bond and be kinder to each other.

"It's not a prune tree, they pruned the tree."

Alex shares that Haley has misunderstood the tree outside

Alex and Haley standing outside on Modern Family

In a hilarious scene, Haley says that her bedroom is too bright in the morning because a prune tree was cut down, and Alex says that "pruning the tree" means trimming a regular tree.

There are many moments on Modern Family when Alex's desire to do well in school makes her life more difficult, like in season 5 when she struggles with perfectionism and worry. But for the most part, when Alex jokes about Haley's ditzy personality, fans can't help but laugh at the difference between the sisters.

"Classy start to a classy life."

Haley learns that Phil and Claire conceived her while seeing Duran Duran

The Dunphys sitting in the living room talking on Modern Family

Claire and Phil's Modern Family relationship begins when they enjoy a Duran Duran show and conceive Haley, deciding to stay together and start a family and realizing how much they love each other. When Haley learns this part of her story, Alex jokes that it's "classy."

Alex's statement is funny and said at the right moment, as this makes Haley grimace but it's ultimately the best possible thing to say, as Haley stops herself from overthinking what she has heard. Phil and Claire never want Haley to think that they weren't happy and excited about her arrival, and Alex knows that too, so she stops herself before she says something too mean.

"Seriously, Haley, you think you are the coolest person ever!"

Alex gets upset with Haley in season 3

Alex and Haley holding boxes and fighting on Modern Family

There are many moments when Alex and Haley are so frustrated with each other that they can't help but yell, something that anyone with a sibling has most likely experienced. Alex comes right out and tells Haley that she shouldn't be conceited and should think about other people's feelings more.

While Haley doesn't love hearing this, her sister's words do stay with her, and the characters eventually come to a place where they can chat without yelling or fighting. It's really sweet seeing their relationship shift over the years.

"You inventing new illnesses to get out of PE."

Alex and Haley reflect on growing up together

Haley Alex and Luke in Modern Family

Alex and Haley share a sweet moment before the sitcom ends when they go through their old toys and belongings. They want to prank Luke and pretend that he's a dog like they did once, but they also reminiscence about spending time together when they were younger.

The characters talk about how Alex was always studying or reading and Haley would come up with excuses to not have to attend gym class. This funny exchange speaks to the way that the sisters see themselves and each other: Alex as the smart "nerd" and Haley as the ditzy one who doesn't care about school. But now that they're older, they realize that they're each intelligent and interesting in their own ways.

"You say that but do you mean it?"

Haley doesn't understand Alex's It's A Wonderful Life reference

The Dunphy family standing together on Christmas on Modern Family

Modern Family fans sympathize with Alex in many cases, but sometimes she tries too hard to prove that she knows more about the world than Haley. In this funny scene, Haley doesn't realize that she's talking about the plot of It's A Wonderful Life, and thinks that Alex is sharing how much she enjoys her own life.

This endearing exchange shows that while the siblings don't always understand each other and they're living totally different lives, with Alex focused on school and success and Haley wanting to have fun, they still mean a lot to each other.

"Usually when I hear people talking like this, they're walking through a Taco Bell drive-through."

The family finds Alex walking around outside worried about graduation

Alex and Haley talking on Modern Family

The family drives by Alex walking around looking lost and confused as her graduation day is approaching and she's scared of life after high school. Before Jay gives some good advice, Haley jokes about seeing people looking like Alex when they're grabbing some fast food.

Although Haley empathizes with Alex's worries about what her life will look like, Haley can't help but crack a joke and try to lighten the moment. Haley's sense of humor contrasts with Alex's serious outlook on life as they approach similar situations in opposite ways.

"Oh, what a joyous..."

Haley tells Alex and Luke that she's pregnant

Haley wearing overalls while pregnant on Modern Family

One of the most unforgettable aspects of Haley and Dylan Marshall's Modern Family relationship is in the final two seasons when Haley becomes pregnant with twins and the characters learn the ins and outs of parenthood. When Haley tells her siblings that she's expecting, Alex is shocked and tries to be polite and nice when she learns that Dylan is the father.

Alex's words have great comedic timing and she proves that at this point in the sitcom, she's trying her best to be sweet and supportive of her older sister. Alex knows that they have been through a lot and haven't always been kind, and she knows that Haley will be a wonderful mom.

"You sound like mom. I don't know what I'm gonna do after high school!"

Haley and Alex fight in season 3

Haley staring off-camera on set of Modern Family

When Alex asks Haley if she will become a "career criminal," Haley gets upset about being unsure of her future path. Haley's quote explains the core of Alex and Haley's sibling bond: while they're going in different directions, they always find time to talk and be in each other's lives.

It might take a long time for the characters to become closer, but in the final season, they realize that they've always been a significant part of each other's stories. Alex has appreciated Haley's optimistic personality and Haley loves how smart Alex is as Alex inspires Haley to go after her own goals.

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