Both stars shared with fans that they have each lost a precious pooch.
"RIP NICKY O BOY - r miami born rescue dog - loyal smart nearly perfect for over a dozen years," O'Donnell tweeted on Friday along with a picture of the cute canine.
Meanwhile, Cosgrove revealed on Sunday that her poodle—and life-long friend—had died as well.
"My dog, Pearl, passed away today," the iCarly star tweeted. "She was there on my first day of kindergarten and my first day of college. I'll love you forever."
RIP, Nicky and Pearl!