Meghan Trainor can’t believe she’s the mom of a 3-year-old!

On Thursday, the “Mother” singer, 30, marked her older son Riley’s third birthday with a sweet tribute on Instagram.

The post featured a carousel of family images and solo snaps of Riley, beginning with a smiling photo of Trainor and her actor husband Daryl Sabara cuddling up to their little boy.

“HOW IS MY BABY 3 YEARS OLD?!🥳🎂🎉,” Trainor captioned her celebratory post. “RILEY, YOU ARE SO LOVED! YOU ARE THE SWEETEST, FUNNIEST, MOST DELICIOUS LITTLE HUMAN. YOU HAVE MY WHOLE HEART ♥️ MAMA LOVES YOU TO THE MOON AND BACK! 🚀.”

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Other pictures included Riley flashing a cheeky grin at the camera and looking through a magnifying glass, as well as snaps of him posing with his younger brother Barry Bruce, 7 months.

The carousel also featured two photos of the family of four posing together, with one showing them dressed in matching cream knitwear.

“🥹🥹🥹 I’m not crying you’re crying,” wrote Sabara, 31, in the comments section, while heiress and DJ Paris Hilton simply commented with a heart-eyes emoji. 

“I can’t w how cuuuuuuute,” added singer Jewel, as actress Nia Vardalos chimed in, „What on earth, this is THE CUTE FAMILY!!! ❤”

Last month, Trainor opened up to PEOPLE about Riley’s big day and her plans, including his very specific request for his birthday cake.

„Every time I want to try to plan something, I’m always like, ‘Eh, germs and people, and I don’t want to … He’s not going to remember this one yet,’ ” said the mother of two. „But I do know that for a cake, he really wants it to be a car, a cake car.”

„And it has to be specific. It has to be our white car that we have,” Trainor continued. “So I am literally hiring this amazing cake creator to make our Rivian car into a cake.”

„I was like, ‘What about Lightning McQueen car?’ And he was like, ‘No, white car,’ ” she laughed, referring to the popular character voiced by Owen Wilson in the Cars animated-film franchise.