For the Knowles family this has been a big week. Singing superstar Beyonce welcomed her first child on Saturday night, baby girl Blue Ivy Carter. Not only did her sister Solange Knowles become an aunt to the baby girl, she is now also officially a model.

Solange just signed with Next Models, Vogue UK reported. Next Models also represents the up and coming faces Lana Del Rey, Sarah Ruba and Suki Waterhouse.

Artistic expression is invaluable to me in all walks of my career and I am so excited to continue to develop this path along with such an amazing team at Next Model Management, Knowles told Vogue. I feel right at home working with people who have worked beside such creative forces in the world.

Knowles is no newbie to the spotlight. She has had three solo albums thus far and has been featured in ad campaigns for Rimmel, Armani Jeans and her family's House of Dereon line. Next month she will become Vogue.com's new Today I'm Wearing star. Previously, famous fashionistas like Alexa Chung, Lily Aldridge and Alessandra Ambrosio have been featured.

We are delighted to be working with Solange, said Next global publicist Katy Moseley. She is hugely popular and beautiful, with so many brilliant ideas and creative energy.

Though the signing was extraordinary for her, Solange's most wonderful news of the weekend was perhaps her new role as aunt. Solange, who has a son of her own, tweeted about her niece after the birth was announced: The most beautiful girl in the world.

Beyonce gave birth at Lenox Hill Hospital in New York City with her family by her side.