Mix of heartwarming and funny in the pilot after the new CSI makes a wrong turn out of autopsy on her way to the bathroom and ends up in the morgue and gets trapped inside. Grissom rescues the terrified newbie and, when she says she could hear the corpses breathing, he turns to the door to the morgue and yells, "You assholes!" at the bodies.
The episode "Boom" when Grissom adds a newspaper clipping of Dominic the security guard to the wall of dead police officers.
Grissom and Sara meeting up in the rainforest after the former leaves the show.
The end of "Sounds of Silence." Seeing Grissom and Dr. Gilbert, the lady who headed up the institute for the deaf, just sitting in the park, having a conversation through sign-language. Both of them are smiling and enjoying each other's company, with Dr. Gilbert laughing every so often and correcting Gil's signing as he's "a little rusty." It's little moments like this that keep the show from being completely dark, moments where, whether amid or in the aftermath of the worst of society, there shines a glimmer of humanity.
Sara's mother-in-law bringing her a potted plant as a peace offering, after spending the whole episode basically implying she isn't good enough for Grissom, and the two of them having a nice shared moment with Grissom on a webcam.
In "Cold Blooded" Hodges and Langston's kid-in-a-candy-store grins when they arrive at the Walking With Dinosaurs show.
Nick and Doc Robbins find a dead girl, heavily pregnant with her baby still moving. Robbins does a hasty Caesarean and there's a few tense moments while he and Nick try to resuscitate the baby... and then she starts crying like any healthy baby at birth. Even with the circumstances, the looks on the men's faces are heartmelting.
At the end of the episode, Nick brings the baby's father to hold his baby daughter.
In a S2 episode, Sara tells Grissom she is weighing the option of taking another job due to feeling that Grissom lacked a level of respect and understanding when dealing with her and the rest of the team. At the end of the episode, Grissom still isn't really taking the issue all that seriously until Catherine emphasizes how much he distances himself from everything. This causes Grissom to understand a little bit about how his aloofness affects everyone and sends flowers to Sara, making sure that the card reads it's from him.
When Sara's alcohol abuse takes its toll and eventually gets her suspended with her job on the line, Grissom requests Ecklie that Sara be placed on his shift with him taking full responsibility for her. He then goes to her house, where she's still emotionally turbulent until a patient Grissom is able to get her to talk about her Dark and Troubled Past.
Borderlines on Tear Jerker, in "Code Blue Plate Special", the elderly couple killed in the diner are seen lying on the floor holding hands.
"Play Dead" also borderlines on Tear Jerker for those that have seen videos or pictures of dogs' loyalty to their owners even after death, but it's definitely one for dog lovers and owners when Nick adopts K-9 Sam upon hearing Sam's retirement.
The relationship between Conrad Ecklie and his daughter, CSI Morgan Brody, is a sort of arc CMOH. When she first joins the team she hates her father, due to his Parental Abandonment after the divorce when she was 14. She slowly starts to come around to him, realizing that he's not the Jerkass he used to be, and she eventually comes to forgive him and start treating him more like a father that she actually loves and truly cares about. Her finally admitting that she loves him in the S13 premiere was very heartwarming.