Jamie Lynn Spears‘ cousin Alli Sims says the 17-year-old will make a great mom to daughter Maddie.

“I’m sure the baby’s beautiful, and I’m so glad everybody’s healthy and doing well,” Sims told Usmagazine at an after-party for Wanted in Los Angeles on Thursday.

“I just wish them all the happiness in the world,” she said. “I know they’re going to have so much fun.”

Sims — who said she is still “great friends” with Britney (who’s recording a new album) — added that she plans on sending “something cute.

“I’m sure they’re doing great,” she told Us. “I know they’re just so excited.”

Maddie was born Thursday at Mississippi Southwest Regional Medical Center in McComb, Mississippi.

She weighed 7 lbs., 11 ounces.

Jamie Lynn Spears and Casey Aldridge’s decision to name their newborn daughter Maddie Briann is “a surprising choice,” baby name expert Pam Satran, coauthor of baby-naming guides Cool Names and The Baby Name Bible, tells Joynews.

“[Maddie is] cute but nearly old-fashioned at this point,” Satran says. “The nickname Maddie has been popular in its own right since the 1980s, when it was the name used by the character played by Cybill Shepherd in Moonlighting.”

The name is short for Madeline (the French variation of Magdalen, which is Greek for “high tower) or Madison (of English origin, meaning “son of the mighty warrior”), which was a top name several years ago, Satran explains.

“Both Jamie and Maddie are ’80s-style nickname names,” Satran adds. “Rather than mother and daughter, they sound like classmates – co-captains of the cheerleading squad!”

As for Maddie’s middle name, Briann, Satran reveals its “a modern feminization of Brian, Irish for ’strong.’

Briann, Brian, Brianne and Brianna have been trending downward over the past several years, Satran points out.

Jamie Lynn gave birth to Maddie Thursday at Mississippi Southwest Regional Medical Center in McComb, Mississippi. Maddie – Jamie Lynn and Aldridge’s first child – weighed 7 lbs., 11 ounces.

Tell Us: Do you like the name Maddie Briann?

Jennifer Garner appreciates her fans – even when they ask the tough questions. Asked, “When are you going to have another [child]?” during a break in filming This Side of Truth last Friday, the 36-year-old actress laughed off the unexpected query. “Sometime,” she replied. “I don’t know. I have to think about that one.”

Garner – who was in Lowell, Mass., shooting the flick (costarring Tina Fey and Ricky Gervais) – made sure to spend quality time with fans of all ages. But she paid special attention to her youngest admirers.

“I have to say hi to the girls,” she said, heading over to sign autographs for a crowd. She made sure all the children got some face time.

Ben Affleck’s other half asked one little girl, “Are you a swimmer?” before revealing, “I was a swimmer when I was your age.”

Other young fans asked about daughter Violet, 2. “She’s good,” replied Garner, who fended off compliments about her appearance with some good-natured modesty. She joked to one admirer: “That’s what five hours of hair and makeup will do for you!”