Pink and Carey Hart may be busy with their newborn son Jameson Moon, but they are making sure their daughter Willow feels special too

By Jen Juneau
January 16, 2017 12:20 PM

While new babies are certainly a cause for celebration, their siblings deserve the fanfare too!

On Sunday, Pink and husband Carey Hart shared a photo from a big-sister party they threw for their 5½-year-old daughter Willow Sage, who just helped welcome her little brother Jameson Moon into the world on Dec. 26.

“Congrats Big Sis! #bigsisterparty,” the singer, 37, captioned a photo of herself, Willow and a snoozing Jameson.

Mother and daughter flash their pearly whites at the camera, amidst a background of festive balloons.

And no party is complete without cake. Willow’s confection is decorated to say “Congrats Big Sis!” above two sibling birds: a pink one that appears to be blowing kisses to a smaller green one.

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Since Jameson’s birth, the proud new mom of two has been giving her followers a glimpse into her life as a family of four.

“Happy New Year #newlove #newlife #newenergy #newhope #newday,” she wrote next to an early January snap of a beaming Willow holding her new baby brother.

“The Harts thank you for your love and we send it back to you in spades,” she added.

RELATED VIDEO: Pink and Carey Hart Welcome Second Child Jameson Moon

The girl of the hour was more than ready for her duties as a big sister, her parents have made clear in the past.

“Dry Runs,” Pink captioned a photo taken before Jameson’s birth of Willow practicing diaper changing on a baby doll.

“She built a bicycle for him or her,” Hart, 41, told PEOPLE of his daughter in early December. “So we’re going to finish it up after No. 2 shows up.”