The pop star announced the arrival of Parker with footballer Wayne Bridge on Twitter.com on Friday (18Oct13), informing fans that both mother and baby were happy and healthy.
Her bandmates Rochelle Humes, Mollie King, and Una Foden were quick to tweet their delight at the news.
Humes writes, "Massive congrats to @frankiethesats and Wayney! The best text to wake up to this morning... lock up your daughters Parker Bridge has arrived".
Her husband, JLS star Marvin Humes, also tweeted his well wishes.
King adds, "So unbelievably happy for @FrankieTheSats & Wayne on this incredible day! I need to meet little Parker, I can't wait! I love him already," and Foden, formerly Una Healy, writes, "Huge congratulations to @FrankieTheSats and Wayne on the the birth of their darling baby boy Parker, so so excited to meet him!"