Justin Bieber's mother celebrates arrival of Grandson: 'OH MY HEART'

Justin Bieber’s mother Pattie Mallette is in seventh heaven as her family is growing.

Shortly after the Baby hitmaker announced that he had welcomed his first baby with his wife, Hailey Bieber, on Friday, August 23, Mallette, 49, took to Instagram to express her excitement about becoming a grandmother

she reposted her son’s post on her Instagram stories with an endearing note that read, "OH MY HEART."

"WELCOME BABY JACK! I LOVE YOU SO MUCH [series of crying emoji]," Mallette, also an author, added in the caption, referring to the baby as a miracle.

"THANK THE LORD. WHAT A MIRACLE! [dancing girl and celebrations emoji]," she added over the photo itself.

Prior to his mother’s celebratory social media update, Justin posted an adorable snapshot of his new-born son. In the photo, a tiny foot is swaddled in a cosy blanket, with Hailey’s perfectly manicured fingers gently caressing it.

"WELCOME HOME JACK BLUES BIEBER," punctuated with a bear emoji, the 30-year-old pop sensation wrote in the caption.

The couple announced their pregnancy on May 9, revealing that the Rhode mogul was already six months along.