Just a few days after Spencer’s death, on what would have been the Emmy-winning actor’s 59th birthday, the whole West Wing crew and cast gathered at Spencer’s empty house for an impromptu memorial. “It was very helpful for us to talk about him and we even had a birthday cake for John.”- Kristin Chenoweth
That would have been four days later, according to IMDb; he died on Dec. 16, 2005 and his birthday was Dec. 20.
I was touched to see all the secondary characters in the screenshots from “Requiem” above. I know they’re actors who naturally want to work, and that Wells and Co. didn’t have to bring back Ainsley, for example. I choose to interpret it as John Spencer’s fellow actors paying tribute to him as much as “we want your character to appear at Leo’s funeral.”