Britney Spears and her family are "thrilled" with the arrival of Jamie Lynn's newborn daughter, reports proud grandfather Jamie.

The 17-year-old sister of pop star Britney gave birth to Maddie Briann, her first child with fiance Casey Aldridge, at Mississippi Southwest Regional Medical Center in McComb, Miss., on Thursday.

And family patriarch Jamie, who was said to be present at the birth, insists the entire family are delighted with the newest member of their clan.

He tells Life and Style magazine, "We're thrilled, we're all absolutely thrilled."

Spears and Aldrige became engaged in March. The teen star stunned the Spears family when she announced her pregnancy news last year, at the age of 16. They had reportedly been delaying their wedding until after the birth of their child.