This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / Drake & Josh
"Josh is Done". Even sadder after the drama that ensued years later when, in real life, Drake didn't receive an invitation to Josh's wedding, essentially inverting the episode's premise (they patched things up later, however).
Drake's breakdown when his life falls apart without Josh leading to an embarrassing incident in the science room.
Drake: I need you more than you need me! I need you WAY more than you need me! I'm sorry I made you late for your exam! I'm sorry I ran over your bike! I'm sorry I'm probably the worst brother in the world, and you're way better off without me! I just need you to understand...(stammers) Sorry, Josh. I'm sorry.(leaves)