Pretty Little Liars is a dramatic teen TV series that aired from 2010 through 2017. The series may have ended in 2017, but that doesn't mean that every storyline and question that the series opened up to viewers was answered before the credits rolled for the final time. The series had so many twists and turns throughout the course of the seven seasons that aired that it's definitely no surprise that there were some things that were forgotten by the writers and even some of the viewers by the time the show ended.

Related: Pretty Little Liars: 5 Of The Creepiest Messages From “A” (& 5 Of The Lamest)

The series follows a group of friends who become targeted by a mysterious figure known only as "A" after the disappearance of one of their friends. This mysterious figure seems to know all their secrets and the identity of "A" is a huge plot point throughout the course of the series. There were definitely a ton of surprises in the show, but there are also quite a few storylines that were either forgotten or were randomly changed as the show went on.

Ezra's Diary

As anyone who has seen Pretty Little Liars will know, Alison had been missing for exactly a year prior to the start of the series. In this time, Hanna had a huge makeover, Aria and her family moved to Iceland, and their entire friend group kind of fell apart. Aria moved back to Rosewood at the beginning of the series, but she had only been away for one year.

When Ezra's diary was discovered, the fact that he had been writing a true crime novel about Alison was a huge reveal. But, there was one thing many fans didn't notice among all the massive plot twists. In his diary, he referenced the fact that Aria had been living in Iceland for three years when she had actually only been there for one.

Hanna & Mona

Hanna and Mona shopping on Pretty Little Liars

How long had Hanna and Mona been friends? Well, that depends on what episode you're watching. Although those two became the queen bees of their school after Alison disappeared, the writers couldn't seem to keep straight how long they had known each other and been besties.

In the second season, it was implied that Hanna's parents had gotten a divorce during the summer between 8th and 9th grade. During the fourth season, Hanna mentions that Mona had taken her shopping all the time during the summer her dad left even though they had only started being friends in 10th grade. And to make things even more confusing, a season 6 episode mentions that they'd been friends since 7th grade. Talk about complicated!

Ravenswood

We all know that the Halloween episodes were apparently not entirely canon. That's why the fact that Ashley Marin saw a ghost and then never told anyone won't be appearing on this list. But, Ravenswood was a spin-off based in a location that was referenced outside of the Halloween episodes, so it's totally fair game.

Related: 10 Plot Twists That Hurt Pretty Little Liars

In the short-lived spin-off series Ravenswood, Caleb moved to a nearby town by the same name. This series was eerie and the people of this town were totally strange, but nothing was stranger than the fact that Caleb saw his own face on a tombstone in Ravenswood. Unfortunately, the show was canceled and Caleb came back to Pretty Little Liars with no explanation for what was going on there.

Ashley & Mrs. Potter

According to the show's timeline, Ashley Marin took a job at the bank at some time in 2008. In an episode set in 2010, an older woman named Mrs. Potter came to deposit her cash in her safety deposit box, an event that Ashley said happened "once every year."

While it's possible that Mrs. Potter really did come to the bank to put her cash in her safety deposit box every year, there's no way that Ashley saw it happen more than once or twice in the past. So, why was she talking about the event as though it had been going on for a decade or more?

CeCe Sneaking Into Radley

In general, CeCe is a character that has a lot of continuity issues. A major one is the fact that she once snuck into Radley with a forged visitor pass that Wren gave her. Wren was definitely a pretty questionable character throughout the entire series but for once, this issue isn't focused on him.

CeCe was a patient at Radley. So, why did she need to sneak in to visit someone? How did no one recognize her and turn down her forged pass? Although this was likely a plot point that was invented to make CeCe seem more sneaky and conniving, it became completely nonsensical as we learned more about CeCe's history.

Emily & Paige's Sing-Along

Since Pretty Little Liars aired through 2017, it can sometimes be hard to remember that the show is actually technically set in previous years. There are quite a few minor things that happened or were referenced in the series that make no sense with the show's timeline, but this is one of the biggest ones.

Related: Pretty Little Liars: 10 Of The Biggest Differences Between The Show & Books

In the 5th season of the series, Emily and Paige went to a Frozen-themed sing-along. It was totally adorable watching the two of them sing "Let It Go" together, right? Sure, until you remember that Frozen was released in 2013 and this episode was supposed to be set in 2011.

The Longest November

The lack of major holidays being referenced throughout the series can sometimes make it hard to get a good frame of reference for what day or even month it is in Pretty Little Liars. But, this isn't really a problem until another holiday comes up and viewers realize how much had happened since the last major holiday reference.

The worst offender for this is the fact that the middle of the 3rd season through the middle of the 5th season was all taking place in November. We know this because of the end of the Halloween special kicking off the month and the following Thanksgiving finally taking place in the 12th episode of the 5th season.

CeCe's Roommate

Cece in a coffe shop turns around in Pretty Little Liars

CeCe was a patient at Radley, but she was still allowed out of the institute at the discretion of her doctors and therapists. Part of her being allowed to leave was the fact that she was allowed to go to UPenn as a student. The show explained how she was allowed out to attend her classes and this is not a continuity error.

What's not explained is the fact that CeCe apparently had a roommate at UPenn. When a character was originally introduced as her college roommate, it seemed like no big deal. But, when the fact that she was actually a Radley patient was later explained, it became confusing how she had a roommate despite clearly not living on campus.

Is Duck Vegetarian?

Several times throughout the series, Aria hinted at being vegan. She was always ordering soy lattes, she was never seen ordering anything with meat or dairy, and it was clearly a characteristic that this character had in order to help flesh her out and make her feel like a real person.

But, in the 7th season, it seems like the writers totally forgot about the fact that Aria had quietly been a vegan the entire time. While talking to the other Liars, Aria ordered duck at their meal. Did Aria decide to switch up her diet at some point in the series?

An A-Team Full Of Doctors

The A-Team did some pretty terrible things to the Liars throughout the course of the series. While it started out with clever text messages, it escalated pretty quickly and got to a lot more dramatic and life-threatening acts.

At one point, a member of The A-Team even did oral surgery on Hanna and left a note inside one of her teeth. How did they know what they were doing? Where did "A" get this medical knowledge and manage to do such exact dental work?

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