For 12 seasons, we had the opportunity to learn and grow with the characters of The Big Bang Theory. We saw Amy and Sheldon get their Nobel Prize, Penny and Leonard finally got married (and found themselves pregnant), Howard finally found his dream girl in Bernadette, and Raj found a passion for working at the planetarium. Our favorite friend-group has grown up right in front of our eyes and we miss watching new episodes to see what the characters are doing now. To reminisce on our favorite moments, let's take a look at 10 things we miss most about it.

SHELDON AND PENNY'S BANTER

What started off as two strangers who couldn't be any more different grew into a brother/sister relationship that fans cherished. After the first episode of the first season aired, there was no way any of us could have imagined the friendship that was blossoming.

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The two have taken care of each other when they were sick, have taken each other to work, and have helped each other tremendously. Sheldon helped Penny with her Penny Blossom line and Penny helped Sheldon with how to act "normal." This friendship was one of TV's best.

AMY'S OBSESSION WITH PENNY

Painting of Amy and Penny that Amy gave her in TBBT

This hilarious relationship between Amy and Penny only grew over time. Granted, Amy's character development changed as seasons went on (for the better), making her more life-like than robotic. After the two first meet on Amy's first date with Sheldon, they begin seeing more of each other thanks to being neighbors with the guys. The first time they become closer than acquaintances is when Amy invites herself over to Penny's sleepover with Bernadette. From there, Amy grew an obsession over having a hot best friend that only proceeded to get funnier.

SHELDON AND AMY BECOMING MORE COMFORTABLE WITH EACH OTHER

Amy and Sheldon were a little weird at first but the longer the series went on the more comfortable the two became. Just to prove how slow these two were moving, they didn't sleep together until season nine!

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But before Sheldon was even comfortable enough to do that with Amy, we saw them learn from each other. Sheldon always claims he knows more than most people but he seemed very taken by Amy when she had facts that trumped his. And over 12 seasons, we saw them learn to live together, get engaged, plan a wedding, and even win a Nobel prize for their Super Asymmetry theory.

HOWARD'S PICKUP LINES

Fans love Howard and Bernadette's relationship, especially as parents. The two really balance each other out and no one is giddier around Howard's weird lines than his wife. However, before he took Bernadette's heart, he was a very passionate man with the ladies. Well, he wished he was anyway. Anytime a pretty girl walked in his direction he thought they were giving him the signal to hit on them. In his defense—after getting in an argument with Penny over his demoralizing behavior—if he didn't try hard, what other choice did he have? He wasn't the tallest, the biggest, or most handsome, so he had to go the extra mile to hook a woman with his charms!

RAJ AND HOWARD'S BROMANCE

Howard and Raj kiss each other in The Big Bang Theory

Between the iconic friendships of Leonard and Sheldon and Sheldon and Penny, Raj and Howard are close behind. Before Howard found love, he and Raj were each other's sidekicks. They would go out on Ladies' Nights and try to pick up any woman who would look at them. When both of them were continuously turned down, they always came home together.

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It was due to their ill-attempts at getting women that made them closer than BFFs. In fact, many fans thought the Big Bang writers were going to make these two date. But as we know, Howard loves the ladies and Raj sure did try.

HOWARD'S RELATIONSHIP WITH HIS MOM

Howard standing over a fake version of his mom on TBT

Carol Ann Susi played Howard's mom Debbie in The Big Bang Theory. We never saw her but we always heard her behind the scenes yelling at Howard. These two were the classic mother and son relationship where the mother doesn't want her son to leave the nest. Before Raj and Bernadette came into the picture, his mom was all Howard had.

In the eighth season, Carol Ann Susi passed away in real life which made the writers write her character off the show. After all, no one can replicate Debbie's voice. However, in her healthier days, seeing Howard and Debbie yell and love and eat made each episode better.

SHELDON SLOWLY UNDERSTANDING SARCASM

Sheldon and Penny in the hospital looking mad on The Big Bang Theory

Sheldon learned a lot from his friend group, especially Penny. He may be a genius with a high IQ but there are some "normal" things that he just can't master like sarcasm. After hanging out with Leonard and Penny, he can't decipher when the two are being serious or are joking. It's funny to the audience—because we can pick up on their sarcasm—but Sheldon gets quite flustered by it. Were his friends joking or being serious? After a few attempts, we see Sheldon slowly learning sarcasm and not taking Penny's jokes so seriously.

THE BEEF BETWEEN SHELDON AND LEONARD'S PARENTS

Maternal Combustion The Big Bang Theory

The Big Bang Theory world couldn't wait for Sheldon's Catholic mother to meet Leornard's scientific mother. The two were extremely different from their own passions contradicting each other greatly. We've seen their mothers get together a few times but it's their first meeting that really struck a chord with the audience.

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Sheldon's mother kept making God references while Leonard's mom thought she was kidding. The two spat insults at one another while trying to prove their point, which was a real sore spot for roommates Leonard and Sheldon. It's also comical that Leonard and Sheldon's parenting roles should totally be switched. Sheldon got along with Leonard's mom perfectly and Leonard felt safe and loved by Sheldon's mom.

THE CAT AND MOUSE RELATIONSHIP BETWEEN PENNY AND LEONARD

Leonard and Penny talking in her apartment after their Valentine's Day date in The Big Bang Theory

We saw Leonard fall in love with Penny the first day he saw her unpacking across the hall. We've seen these two try date (and break up), become jealous of new lovers, take care of Sheldon as if he were their own, fall back in love, get engaged, and get married. We've followed their love story from the beginning and although the show ended with many answers to their relationship, we still miss seeing their odd relationship and how it works.

MOST IMPORTANTLY: DINNERS IN APARTMENT 4A

The finale of TBBT - the final scene of the characters eating

In every episode, we always saw the gang eating dinner in Apartment 4A - Leonard and Sheldon's apartment. Due to Sheldon's quirks, dinner in their apartment was the only option. From pizza to Chinese, we saw this group of seven talk about the matters of the day at their own laid-back dinner. What's even more likable about these scenes is that each member of the group has their own spot. Sheldon always whined about having his spot on the couch but when you think about it, they all had their own spot (with poor Raj forever being on the floor).

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