Megan apologising to Sanjay at the end of "Susan Loogie".
Pretty much the entire premise of "Bros of a Feather".
The end of "Trouble Dare" where Mark Summers says, "Good night, old friend" to Harvey. It'll touch the heart of those who grew up when Nickelodeon had Double Dare (both the version with kids as the contestants and the ones with families).
Nine words: Everything cool I do I do it with you
Sanjay himself can be utterly adorable at times, especially as a toddler (baby?) in the leaked episode, "Beauty and the Beard".