Kim Kardashian took Mason out to celebrate his 5th birthday Credit: Courtesy Kim Kardashian

Too cute! Auntie Kim Kardashian came to the rescue to make sure nephew Mason Disick had a fifth birthday to remember, even though his mom, Kourtney Kardashian, was in the hospital giving birth to his new little brother.

The newest member of the Kardashian clan came into the world on Sunday, Dec. 14 (his older brother's fifth birthday), bringing the number of kids Kourtney and longtime love Scott Disick now share to three.

But concerned to make sure little Mason, 5, and his younger sister Penelope, 2, didn't miss out on celebrations just because there was a new baby in the household, Kim and husband Kanye West took the kids (including their own daughter North, 18 months) to a birthday Disney on Ice performance at Los Angeles' Staples Center on Sunday afternoon.

The reality TV star shared a host of adorable photographs of the family outing via Instagram, including one of the cute little tots holding hands with each other in the carpark, full of anticipation.

"Disney on Ice #Mason #Zeplin #Penelope #North #BestFriends," Kim captioned the snap of Mason, Penelope, North, and her friend and makeup artist Joyce Bonelli's little boy ZeplinSee more adorable photos from the birthday party.

In another hilarious snap, North (who eschewed the pink Disney princess look in favor of an all-black outfit) is seen carrying mom's Chanel handbag, "She's ready!" proud mom Kim captioned the snap.

She's ready!

Une photo publiée par Kim Kardashian West (@kimkardashian) le Déc. 12, 2014 at 4:25 PST

A third photo shows the whole gang (excluding Kanye, who was presumably behind the camera, but including Kim's pal Ciara and her little boy, Future) looking happy somewhere inside the Staples Center. Birthday boy Mason wore cute Disney ears and the whole party looks like they had a blast.

This was an adventure! Try getting 5 kids to look and smile #DisneyOnIce

A photo posted by Kim Kardashian West (@kimkardashian) on Dec 12, 2014 at 6:25pm PST

"This was an adventure!" Kim wrote, "Try getting 5 kids to look and smile #DisneyOnIce."

During the show, the Kardashian brood sat in the front row and Kim took her role as mom and aunt very seriously. Little North sat on mom Kim's knee with birthday boy Mason right next to her, and his little sister Penelope in the next seat along. Kanye took the seat on Kim's other side and was in charge of making sure the little ones were fed.

"Mason and Penelope had big bags of cotton candy," one audience member told Us Weekly. "They seem like an adorable family."