updated 5:13 p.m. ET June 19, 2008

JACKSON, Miss. - Jamie Lynn Spears gave birth to a baby girl Thursday morning at a south Mississippi hospital, according to a friend of the Spears family.

The friend, who asked not to be identified because the family had not yet announced the baby’s birth, told The Associated Press that the baby was named Maddie Briann and weighed 7 pounds, 11 ounces.

The 17-year-old Jamie Lynn was the star of Nickelodeon’s “Zoey 101,” a sitcom about prep school friends, and is the younger sister of pop star Britney Spears. The Spears family announced in December that Jamie Lynn was pregnant. The father is Casey Aldridge, a pipe-layer from Liberty, Miss. The couple is not married but announced an engagement several months ago.

Ellen Brannan, spokeswoman for Southwest Mississippi Regional Medical Center, in McComb, would not give out any details. “We understand everybody’s interested, but we don’t give out information on anyone. Everyone’s entitled to their privacy,” she said.

The younger Spears lives near Liberty with Aldridge, 19, and has been seen around the small south Mississippi town often as her pregnancy became more apparent. Her family owns a home across the state line in Kentwood, La.

Spears announced her pregnancy through an article in OK! Magazine and was expected to receive a large payday for exclusive pictures of the newborn.

Nickelodeon issued a statement about the birth on Thursday, saying, “We wish her and her family well.” Nickelodeon spokeswoman Marianne Romano said that filming of the fourth and final season of “Zoey 101” was completed last summer before Spears became pregnant.

Spears portrayed Zoey Brooks, a student at Pacific Coast Academy, a campus that had been an exclusive all-boys boarding school until Zoey and a handful of other girls arrived. At the end of the series, Zoey gets the boy — longtime crush Chase (Sean Flynn).

Last fall, Spears spoke to OK! of her and Aldrige's reaction to the pregnancy: “It was a shock for both of us, so unexpected. I was in complete and total shock and so was he.”

Spears initially kept the news to herself when she learned of the pregnancy from an at-home test and subsequent doctor visit, she told the celebrity magazine.

“Only one of my friends knew because I needed to work out what I would do for myself before I let anyone’s opinion affect my decision. Then I told my parents and my friends. I was scared, but I had to do what was right for me,” she said.

Spears broke the news to her mother, Lynne, just before Thanksgiving, the magazine reported.

“She was very upset because it wasn’t what she expected at all,” Spears said. “A week after, she had time to cope with it and became very supportive.”

Lynne Spears, already grandmother to Britney’s young sons, told the magazine: “I didn’t believe it because Jamie Lynn’s always been so conscientious. She’s never late for her curfew. I was in shock. I mean, this is my 16-year-old baby.”

She said her actress daughter, the telegenic heroine of her popular Nickelodeon series, has known Aldridge for years and began dating him in high school.

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