Plus, Kim Kardashian posts new adorable photos of Penelope and North West.
Kourtney Kardashian is moving on with her life.
Following news that the 36-year-old reality star is splitting from her longtime boyfriend, 32-year-old Scott Disick, after nine years together, Kourtney took to Instagram to wish their daughter a happy third birthday without any mention of her ex.
"Happy birthday to the sweetest little girl in the world," Kourtney wrote on Thursday alongside an adorable picture of Penelope eating ice cream in a Tinkerbell costume. "Watching your every little move every day brings me immeasurable happiness."
WATCH: Kris Jenner Says Kourtney Kardashian Is 'Hanging in There' After Scott Disick Split
Kourtney celebrated Penelope's birthday on Wednesday at Disneyland, where the mother-of-three also donned a Tinkerbell get-up. The two spent the day with family, namely, Kim Kardashian and her daughter, 2-year-old North West. "MVP goes to @kimkardashian for hanging with my crazy Disney obsessed self for 12 hours of major madness. #Disneyland," Kourtney wrote about a selfie of the four of them.
Penelope is the middle child of Kourtney and Scott, who are also parents to 5-year-old Mason and 6-month-old Reign. "You forever changed my life and my heart and teach me so much every day," Kourtney wrote about a serious-looking Penelope. "Happy birthday my Tinkerbell angel."
As for where Scott was during his daughter's birthday festivities, the Keeping Up With the Kardashians star hasn't been spotted since last week when news of the split broke, though he reportedly sought help for his well-documented addiction issues as recently as last Sunday. Scott reportedly checked in at a rehabilitation facility in Florida, Us Weekly reports, but checked out the very same day after just hours at the center.
Scott took to Instagram on Wednesday and posted a pretty somber birthday message to his daughter.
"1 of the only things I'm proud off about myself," he wrote. "Happybdayp."
Meanwhile, Kim also took to her Instagram on Thursday to wish Penelope a happy birthday, by posting adorable snapshots of her niece with North.
"Happy Birthday P! I know your bday was yesterday but we were celebrating all day! Thanks for being the best big cousin North always looks up to! I love you!" Kim sweetly wrote.
WATCH: Brody Jenner Reacts to Kourtney and Scott's Split -- He's Had 'Some Issues'
Scott was actually photographed getting touchy-feely with his ex, celeb stylist Chloe Bartoli, in Monte Carlo, prior to his and Kourtney's split. Since then, Kardashian fans have not been kind to Chloe, attacking her through her social media accounts. Watch below: