Lampshaded in Psych when Lassiter tries to win back his estranged wife with sugary-cutesy figurines and an equally nauseating card. When she rejects him, he takes the sugary-cutesy figurines down to the shooting range and happily blows each one away.
Barney & Friends, to most people over the age of four. Some of these folks become parents and the "purple freak" is forgiven as being an instant thirty minute babysitter. Practically everyone loved to hate their signature theme song in particular, so much so that parodies invariably began: "I hate you,..."
Here's Humphrey is this due to the mundane nature of each episode, the cheery kid-sung songs and a host that talks down to the viewers. Is there any surprise that Australian kids between the age of six and sixteen have a strong dislike for him?
Oh boy, Willow and Tara in the early stages of their relationship in Buffy the Vampire Slayer, the episode "Family" being the sappiest episode ever. It ended with the two of them hugging while floating in the air. Thankfully they became a much more realistic couple towards the end of season 5.
Played for Laughs on the Angel episode "Smile Time", where a children's show is stealing souls. Watching one episode Angel hears one of the songs played, begins quivering with rage at how sappy it is before demanding they go all Jihad on the show.
The 10th Kingdom largely avoided this... an exceptional feat for a 10-hour miniseries about fairy tales. But in certain places, the sappiness factor was cranked Up to Eleven. See also: Hearts and butterflies swarming through the air in Kissing Town under a pink, heart-shaped moon. Insulin, STAT. Add in the literal Love Is in the Air, most exemplified by the massive pink heart which appears over Wolf and Virginia's head as they share their first kiss, and the little Cupid girl skipping through the streets dispensing fortunes, and... yeah.
A surprisingly straight example, for a show centered on four cynical Jerkasses (although Kramer and occasionally Elaine could be very well-meaning); some of the child characters who appeared now and then could be pretty sugary. One example being the boy in the hospital Kramer accidentally donated the Yankee birthday card to in the episode "The Wink."
The MTVMiley Cyrus New Year's Special A Miley-Sized Surprise: The Veronicas dressed up as fairies, a high-pitched sugary voice reading horrible poetry with the most Totally Radical rhymes imaginable, and all the gushing about making a difference combined.
The BBC's Robin Hood occasionally strays into this sort of territory with its uplifting messages and such. Then the writers, in their infinite wisdom, decided to have an episode filling in Robin and Guy's backstory. Cue Child!Robin developing his addiction to vomit-inducingly-noble stances while throwing out tax collectors.
This trope is a staple of a video known as the Palate Cleanser on Web Soup, which immediately follows the segment "Things You Can't Un-See."
Play School to most people over the age of four, due to the overly-happy nature of each episode that doesn't deal with negative emotions, the artificial kid-sung songs and presenters who cheat, steal, and only eat junk food.
The various Star Trek spinoffs have several episodes set on the resort planet, Risa. It's supposed to be the Federation's greatest vacation place, but both the environment and the locals are sickeningly nice and hospitable. Justified in-universe by the weather being artificially controlled and the locals' hospitality expressing mainly via free love attitudes.
In-universe, the Doctor's holographic family in the Star Trek: Voyager episode "Real Life" start out like this, but B'Elanna tells him how unrealistic this is, invoking the trope by saying, "I am stopping this before my blood sugar levels overload." When she tells him that he won't learn anything about what actual families are like (his stated reason for running the program) with a family that's programmed to be perfect, he agrees to let her alter the program to make it more realistic (basically by adding random probability factors and giving the family members actual personalities). It does not end well.
Semi-parodied among The Muppets with Bean Bunny. The Muppet that Henson Studios learned to love to hate.
The 1981 episode of The Muppet Show with Linda Ronstadt, particularly the finale, where she sings "When I Grow Too Old To Dream." It's very heavily sentimentalized - resident Jerkass Rizzo the Rat is actually shedding tears as he listens to the song.
Some fans complain that the Tenth Doctor and Rose got like this.
It sort of parodied this trope in the bizarre and controversial story "The Happiness Patrol", from the Classic era. Basically, the Doctor and co. travel to a society where everyone is happy, all the time. Except it's discovered later that being anything but happy is treated as a crime. The TARDIS is painted pink, and one of the villains is a "Kandyman", a sadistic android made entirely out of sugar. One Real Life candy company threatened to sue over his resemblance to their mascot, to top it off.
In an episode of Have I Got News for You, Stephen Fry, upon seeing Victoria and David Beckhams' coat of arms (the motto being something along the lines of Love Friendship), he quipped "sometimes there just isn't enough vomit in the world."
He made the same joke on QI when panelist Clive Anderson's buzzer was the sickeningly saccharine "Everything I Do, I Do It For You" by Bryan Adams.
Animal Planet's Too Cute documentary series contains graphic depictions of CUTENESS.
This was a major complaint about Full House back in the day. But hey, if the show didn't fit this, it wouldn't have been the Trope Namer for Full House Music. Seasons 6, 7, and 8 toned down a bit on this, though, only having that occur whenever Nicky and Alex are involved. On an interesting note, any moment on a show that is overly sappy (even if the show itself is not normally) is called a "Full House Moment" outside of TV Tropes.
Invoked on Mystery Science Theater 3000 with Nummymuffin Coocolbutter, an impossibly adorable pet created by Dr. Forrester so he can take over the world while everyone is preoccupied with one. He ends up getting sucked into the Cuteness Proximity himself before this can happen.
The end of the TV film of The Stand. Stephen King ended the book with a mix of light and dark,but the miniseries really turned up the sentimentality and happier stuff.
Storyteller: Rempletweezer ran the Dinky Tinky shop in the foot of the magic oak tree by the wobbly dum dum bush in the shade of the magic glade known as Dingly Dell. Here he sold contraceptives and... (turns pages anxiously) discipline?... naked?... (turns book sideways, apparently looking at an illustration) With a melon!?
Penelope Garcia from Criminal Minds tends to evoke this in the fans, since in some episodes her cuteness can go Up to Eleven (especially in later seasons). Her wardrobe is always colourful, and her tone is extremely playful, and not just with Derek Morgan. It's lampshaded in "No Way Out II: The Evilution of Frank" by her boss, Aaron "Hotch" Hotchner, when he profiles the team to his boss, Erin Strauss (reviewing his conduct), saying that Garcia fills her room with cute figurines and pictures for her to "remind herself of humanity when faced with the horrors that fill her screens".
The climax of the Frasier episode with Frasier's ex-wife Nanny G. Yes...the stage show. Good grief, the stage show!!!
In the Blackadder the Third episode "Amy and Amiability", Edmund needs Prince George to marry Amy Hardwood, daughter of an industrialist, whose "nosey-wosey is so tiny, sometimes I think the pixies gave it to me!" Coincidentally, this predated by only a few years Hugh Laurie as Bertie Wooster having to get disengaged from Madeline Basset, who Amy might be a parody of (although Madeline lacks Amy's secret double-life as a man-voiced, squirrel-murdering highwayman.
Sesame Street tries to subvert this at every turn, but as characters like Elmo and Abby Cadabby gained popularity, moments like this were unavoidable. The Lighter and Softer spin-off Play With Me Sesame was this trope, full stop. Mainly because it appealed to infants and toddlers instead of preschoolers.