Kylie Jenner is a mother.

After months of speculation, the reality TV star confirmed she welcomed a daughter Feb. 1 at 4:43 p.m. She weighed 8 pounds, 9 ounces.

In September, reports said the 20-year-old TV personality and entrepreneur was pregnant, but she has never publicly spoken about the claims.

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Jenner had been dating rapper Travis Scott, 25, for five months when reports that the two were expecting their first child emerged.

E! News reported Jenner confirmed the news in an Instagram post Sunday.

"I'm sorry for keeping you in the dark through all the assumptions," Jenner wrote. “I understand you’re used to me bringing you along on all my journeys. My pregnancy was one I chose not to do in front of the world. I knew for myself I needed to prepare for this role of a lifetime in the most positive, stress free, and healthy way I knew how. There was no gotcha moment, no big paid reveal I had planned. I knew my baby would feel every stress and every emotion so I chose to do it this way for my little life and our happiness.

“Pregnancy has been the most beautiful, empowering, and life-changing experience I've had in my entire life and I'm actually going to miss it. I appreciate my friends and especially my family for helping me make this special moment as private as we could. My beautiful and healthy baby girl arrived February 1st and I just couldn't wait to share this blessing. I've never felt love and happiness like this I could burst! Thank you for understanding.”

Jenner also shared the past nine months of her life in a video uploaded Sunday to YouTube. The video, called, "To Our Daughter," shows close friends of Jenner sharing how they learned she was pregnant. It also give glimpses of  Jenner's baby shower, her doctor appointments and her whirlwind romance with Scott. One part of the video shows

The end of the video, which is more than 11 minutes, shows a glimpse of the newborn but not her face.

Jenner's daughter is the newest addition to the ever-expanding Kardashian-Jenner family. Her older half-sister, Khloe Kardashian, confirmed she was 6 months pregnant in an Instagram post in December. Kim Kardahian  West and husband Kanye West welcomed her third child, a daughter named Chicago, via surrogate in January.