To note, during the live action segments with Kenan talking about old Nick shows, when he talks about Kenan & Kel, he says with some love in his voice "Give it to my boy, Kel". Considering how many people have stated Kenan and Kel haven't spoken in years, it shows that maybe Kenan still cares for his old cast member.
On May 1, 2013, TeenNick ran the "Rugrats Rap" music video to honor the then-recently deceased Chris Kelly (of the 1990s rap duo Kris Kross).
Similarly, on New Year's Day 2015, the block aired a marathon of Rugrats episodes focusing on Chuckie in memory of his first voice actress Christine Cavanaugh, after the news broke of her untimely death (she had died on December 22 the previous year, but the news didn't break until the 30th).
In 2016, Kenan Thompson, Kel Mitchell, Lori Beth Denberg, Danny Tamberelli and Josh Server got together for an All That reunion. It was as heartwarming (and hilarious) as it sounds.
At one point, they talk about the idea of doing it again in another twenty years and say that they should.