* [[spoiler: "If you come into battle with a hundred undead soldiers to save the day, you're everyone's friend."]] Nico finally feeling accepted.
* [[spoiler:"And it was the best underwater kiss of all time." Certainly heartwarming for the Percy/Annabeth fans, but think about this: Percy has finally earned his reward after four years of absolute torture.]]
* Poseidon [[spoiler: telling Percy that he was his favourite son.]]
** Ditto for [[spoiler: Percy getting a hug from his dad for the first time at the end of ''The Last Olympian''.]]
* Tyson talking about how alone he felt on the streets, and even praying to the gods yielded no results. Then the gods sent him Percy.
** The reveal that the bits of metal Tyson had been tinkering with for all of book 2 was a special shield for Percy.
* Hades being all stunned at the warm welcome he recieves from the other Olympians at the end of book five.
* [[spoiler: Calypso letting Percy go. The fact that she loved him enough to let him go, even though she'd spend thousands of years waiting for a new love which would be ripped away again anyways...]] Also doubles as a major Tear Jerker. ;_;
* [[spoiler: Annabeth taking the knife for Percy in ''The Last Olympian'', and then that entire scene where Percy tells her about his Achilles spot]].
* [[spoiler:Zoe Nightshade]] sacrificing herself for Artemis. Even though Artemis was a goddess and couldn't really be killed, [[spoiler:Zoe]] didn't even hesitate before throwing herself between Atlas and her lady. Artemis' clear anguish after [[spoiler:Zoe]]'s death, coupled with the fact that she chose to give her the highest honor imaginable, preserving her spirit in the stars, adds to the tear-jerking legacy [[spoiler: the lieutenant]] left behind.
** And while we're on Zoe, the fact that she sobs--literally breaks down and sobs--after [[spoiler:Bianca]]'s death is not to be shrugged off. This girl is over two thousand years old, has had more than her fair share of loss, and has known [[spoiler:Bianca]] for less than a week. But [[spoiler:Bianca]] is a [[TrueCompanions Hunter]], and she trusted Zoe to protect her. And she couldn't, and she mourns her loss as if she'd known her a thousand years.
* In ''The Last Olympian'', a very subtle CMOH is when Percy and Annabeth, riding through the city, in the middle of a huge battle to save the world, stop to help people who have fallen asleep in dangerous places, like in front of cars, and put out fires. The end of the world is going on, and they still care enough to stop and make sure people are safe. Because they're heroes, and that's what heroes do.
* Percy breaking the cycle of half-blood arrogance, after learning what Hercules did to Zoe: "If I'm going to survive, it won't be because I've got a lion-skin cloak. ''I'm not Hercules''."
** And later on, Zoe acknowledging the truth of the statement. "You spoke the truth, Percy Jackson. You are nothing like... like Hercules. I am honored that you carry this sword."
** Even more heartwarming when you consider that she gave Riptide to Hercules because she thought he was a true hero, brave and strong and ''noble'', and that she was starting to love him. Percy is all of that and more, and it's clear that Zoe ''does'' care for him--almost as a brother--after everything they went through together.
* To be completely honest, Percy’s relationship with his mother is completely this. There is nothing they don’t share and nothing they won’t to for each other
** Percy's relationship with his new stepfather Paul and Sally's relationship with him as well could also be seen as this; especially after year's of putting up with Smelly Gabe
** Paul asking for Percy's permission to marry Sally, because he thinks that Percy has a right to approve of his mother's new husband, before he ask
** Especially in the Last Olympian when Paul says that he wishes he had Percy's courage to do something incredibly dangerous that could save them all. Percy even says that he doesn't get compliments like that a lot.
* At the end of the fifth book, after the gods are finished rewarding everyone, the cyclopes form an isle while standing at attention, and before Percy leaves Tyson says this.
-->Tyson: Hooray for Percy Jackson, Hero of Olympus, and [[CrowningMomentOfHeartwarming my Big Brother!]]