For the most part, the main characters in Friends are very open with each other, always telling each other their thoughts and feelings. However, every now and then they keep secrets, whether it's something lighthearted or a lot more serious, which can lead to some others being upset.
In fact, there is even an episode dedicated to this in "The One With All The Secrets," which illustrates the hilarious circumstances that can happen when characters keep secrets from one another. However, there are certain things characters keep to themselves that end up being a bigger deal and not always funny, whether it be regarding love or friendship.
Joey's Secret Party
Joey's success in acting is mixed throughout the show, but being part of Days Of Our Lives is a big deal for him -- so much so that he decides to throw a rooftop party for the cast and doesn't tell the rest of his friends about it, mainly because he doesn't want them to be embarrassing him in front of his co-workers with celebrities they like.
Eventually, they find out that it is happening and Joey's big secret is blown, thanks to an answering machine message that Rachel hears. However, Joey then makes this secret even worse by admitting he actually hosts this party every year and comes up with no ways to make his friends not be around for the day.
Chandler Kisses Kathy
Chandler's decision to kiss Joey's girlfriend, Kathy, is one of the worst moments of the series. It's a huge betrayal between the two best friends and something that risks ending their friendship, which is made worse because Chandler keeps the secret to himself for a while.
To his credit, Chandler confesses to Joey himself rather than allowing him to hear it elsewhere. However, he still keeps this secret for a while, opting to tell the rest of the group before he admits it to Joey, which is a mistake on his behalf.
Ben Bumps His Head
Monica and Rachel get the opportunity to look after Ben on their own at one stage, and this leads to them accidentally banging his head. Monica's decision to push him up in the air as a game works well until he hits his head on the wooden beam, leading to him getting a big bump.
The two of them are worried that Ross will be cross they injured his child and they do everything in their power to cover up the situation, which includes dressing him in a new outfit featuring a hat. They opt to not tell Ross about the situation, but he quickly works out what happened when he puts Ben to sleep and sees the bump for himself.
Why Jack & Judy Dislike Chandler
Jack and Judy Geller have known Chandler for a long time due to his friendship with Ross, but that doesn't mean they like him. Despite Chandler being unaware of the situation, Monica and Ross's parents actually dislike him and that is all down to a secret Ross has kept his whole life.
When he tried marijuana at a younger age, Jack and Judy managed to smell it and asked questions. In order to protect himself, he blamed it on Chandler, which is a secret he keeps throughout their lives until he has to confess it.
The I Hate Rachel Club
Guest stars on Friends are always a lot of fun, but Brad Pitt appearing as Will led to the revelation of a major Friends secret from Ross's past. Will didn't get along with Rachel during their time at school as she was mean to him, and that led to him and Ross creating the "I Hate Rachel Green Club."
This is a secret that Ross obviously kept to himself throughout his entire time dating Rachel. The two of them even started a vicious rumor about her during their time at school, and it all comes out during a memorable Thanksgiving meal.
Rachel Buys From Pottery Barn
When Rachel ends up living with Phoebe for a period of time, she makes the decision to buy some new furniture that she likes. The only problem with that is she purchases it all from Pottery Barn, which is a store that Phoebe dislikes, as she prefers her things to be one of a kind.
Because of this, Rachel ends up lying about everything she buys, pretending that there's a story behind it and that the apothecary table actually came from a flea market. It's something she does with good intentions, as she wants the apartment to look nice, but in the end, it does go against what Phoebe believes in.
Monica's Closet
Throughout the series, it is clear that Monica is obsessed with everything being as clean as possible. She wants things to be looking perfect in her apartment and she has no problem telling other people off to keep her apartment tidy, which is why her secret closet is such a big deal.
When Chandler decides to push and see what is behind the door that doesn't open throughout the show, it becomes clear why Monica has it hidden. The room is filled with tons of objects that Monica has no place for, making it a complete mess, which is very out of character for her.
Ross Doesn't Tell Rachel They're Married
Ross and Rachel's decision to get married in Las Vegas isn't a smart one, in hindsight, and it's something they both regret doing when the hangover has cleared. However, for Ross, it is an even bigger issue because he has already been divorced twice in his life.
He is desperate not to have a third divorce to his name, so he makes the decision to not do it. While Rachel trusts that her friend has gone through with the paperwork to end their drunken marriage, that isn't the case, and when she finds out about this secret, Rachel is less than impressed.
Monica & Chandler's Relationship
The relationship between Monica and Chandler is arguably the greatest within the entire series, which all of the characters end up loving. However, when they initially got together, the two of them made the decision to keep their relationship a secret, which leads to them sneaking around.
While that doesn't always go to plan, with their first trip away turning into a disaster due to a car chase and Monica wanting a perfect room, it does lead to some funny scenes. From Joey having to lie in order to keep the relationship a secret to how everyone else finds out, with Phoebe's reaction being the best of the bunch, it ends up being a fun secret on the show.
Ross Has Feelings For Rachel
The love storyline between Ross and Rachel is the heartbeat of Friends from the first episode to the last. While they might not always be in love or be in a relationship, this is the big hook that runs throughout the show, and in season one, Ross's love for Rachel is a huge part of the plot.
However, he keeps it a secret (which he had done his entire life) and opts not to tell her. Whether it's because she has a boyfriend or the time isn't right, Ross decides to keep his feelings hidden. It's a huge secret that the audience is in on, which makes it even better, and Chandler is the one that eventually slips up without Ross even knowing.