Billy Crystal is getting vulnerable about how he's processing the death of close friend Rob Reiner.

"There's so many moments that when something good happens, or [I think] 'Isn't that crazy?' I want to pick up the phone and call [him] and say, 'Did you see it?' Because that's what we would do," the 78-year-old actor said during his April 14 appearance on "The Late Show with Stephen Colbert."

Crystal remembered his "When Harry Met Sally …" director, who died at 78 alongside wife Michele Reiner in a suspected double homicide in December, as "hilarious, devoted, opinionated in the best way, fighting for the truth for our country."

"We could talk about everything. He was an uncle to my kids," Crystal told Colbert.

The "City Slickers" actor, who is promoting his upcoming one-man show on Broadway, also opened up about his final conversations with Reiner during Oscars host Conan O'Brien's Christmas party the night before the Reiners' killings.