The 41-year-old crooner posted a sweet snap showing him cradling the adorable newborn in one arm, while his 7-year-old son, Julian, cozied up to the 1-month-old baby in the other.

And, judging by the look on Julian’s face, he couldn’t be more thrilled to be a big brother!

“Lucky Daddy!” Thicke captioned the cute photo, in which Mia was bundled up in a blanket and appeared to be sucking on her tiny fingers. Julian, whose mother is Thicke’s ex-wife, Paula Patton, meanwhile had a big grin on his face.

The heartwarming post comes just one day after Thicke’s girlfriend, April Love Geary, revealed the first look at Mia’s face on Instagram.

Wearing a pink hoodie that read, “BABY GIRL,” Geary posed with little Mia in her arms and looked fabulous despite giving birth just weeks ago.

“My little love,” she captioned the pic. 

Mia, who is the couple’s first child together, arrived via caesarian at 1:33 p.m. on Feb. 22.