Her son with Louis Tomlinson became a trending topic on Twitter even before his birth on 21 January. However, before the news of her pregnancy was revealed little was known about Brianna Jungwirth. Here's what we do know.
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Briana Jungwirth has just given birth to Freddie Reign Tomlinson
The 24-year-old stylist had a brief relationship with the One Direction star last year. Louis was seen on a string of dates with the American beauty last spring. On 12 May, they were seen holding hands in the back of a car on leaving the Snoop Dogg album release party in Los Angeles.
Briana is based in Calabasas, California – the same exclusive neighbourhood where the Kardashians live. She is thought to have graduated from Agoura High School in 2010. The pretty blonde had been living with her mother Tammi Clark, stepbrother Brett Clark and her little brother Austin.
Her father Joe Jungwirth described her as "shy but strong"
However, Louis has now rented a three-bedroom home for her and their son little Freddie Reign. A source told the Daily Mail: "He thinks Briana will be an amazing mother. It was a surprise at first, but he and Briana are very, very close friends and this has brought them even closer."
Apart from her mother, Briana can count on the support of her father construction boss Joe Jungwirth and his wife successful singer-songwriter Karen Lawrence, who live in Redfield, South Dakota. He and Tammi split up when their daughter was ten and he went on to marry Karen in 2007.
Ahead of the birth she wrote: "So ready for you, my love" on Instagram
When the news broke Joe described his daughter to the Daily Mail as "strong but shy, she's tough but shy", adding: "She's having a tough time with it, it's stressing her out right now, she's texting me all the time."
He went on: "It's a bit of a shock, you know, they're kids, stuff happens, but I'm supporting her. I love her to death and it's all good."
Briana also has the approval of Louis' mother Johannah Deakin and stepfather Dan, who flew out to America to meet her last year. They spent time with her over the July 4th weekend and are said to have attended an ante-natal scan with her and her parents.
Briana nesting in the three-bedroom house Louis leased for her and the baby
As a fan of self-help guides, she spent the last few weeks of her pregnancy trying to be as peaceful as possible. Her Instagram account includes a post showing a page from spiritual guru Eckhart Tolle's book A New Earth.
It read. "How to be at peace now? By making peace with the present moment. The present moment is the field on which the game of life happens. It cannot happen anywhere else.
The book urges readers to discover the secret of the art of living, telling them. "Being one with life is being one with Now. You then realise that you don't live your life but life lives you. Life is the dancer and you are the dance."