Fearne Cotton has become a mother, the Radio 1 DJ announced, to a boy called Rex.
The broadcaster and her partner Jesse Wood announced the news of the baby's arrival on Twitter.
"Jesse and I are over-the-moon to announce the arrival of Rex Rayne Wood born on the 21.2.13," she said.
The star, who has been on maternity leave from her Radio 1 show since just before Christmas, added two heart symbols and wrote "beyond in love".
Cotton, 31, has been dating Wood, the son of Rolling Stones star Ronnie Wood, since 2011.
Model and musician Wood has two children, Arthur and Lola, from his marriage to Tilly Wood.