It's been a busy few days for Britney Spears. Not only was she granted some additional mommy-and-me time with sons Sean Preston, 2, and Jayden James, 20 months, after a court hearing on Tuesday, but she also winged to her hometown of Kentwood, La., to attend the weekend baby shower of her little sister, Jamie Lynn.

"It was wonderful to be able to spend time with her and just be girls again," the 17-year-old mother-to-be bubbled of their reunion in yet another "exclusive interview" with OK! (the mag broke the news of her unforeseen bun in the oven as part of a purported million-dollar deal). "We painted our nails and did stupid stuff, and we had our private time too ... To be able to be in the privacy of our own home and just be sisters again was wonderful."

And just because Britney isn't allowed to be with her tots without a court-appointed monitor watching her every move, that didn't stop her from doling out parenting advice.

"She told me, 'There are going to be some long nights, but it is completely worth it,'" reveals Jamie Lynn, who adds that the closely supervised cautionary tale has already bonded with her fiancé, Casey Aldridge (his mom was among the 30 or so guests at the shower).

"She loves Casey," enthuses JL, who is due next month. "She's met him a bunch of times. They were riding four-wheelers and stuff together. They get along real well."

Brit, who reportedly hadn't seen her expectant sister since October, arrived for the ladies-only shower at the family's Serenity compound empty-handed but promised her sis a gift was already picked out.

"She has a special thing but hasn't given it to me yet," Jamie Lynn tells the magazine. "She won't tell me what it is, but she said she didn't want to give it to me that day. I'm really excited to find out what it is."

As long as it's not a Britney-penned child-rearing guide, we're sure it'll be lovely -- and possibly pink.

Jamie Lynn confirms to OK! that she's expecting a girl, and reassuringly adds that she's been devouring "What to Expect When You're Expecting."

Meanwhile, mom Lynne was apparently as shrewd about planning her teen's shower as she was about making OK! their go-to baby news outlet. The soon-to-pop starlet says Mama Spears "put it all together for me" and invited several of her well-heeled Kentwood friends.

"There were mainly people her age so that way they could get me all the important stuff I need," admits a surprisingly practical Jamie Lynn. "The people my age ... got me the cute stuff."

Her haul included "adorable clothes," she says. "I registered for all the necessities. There is a certain type of bottle I use, Dr. Brown's Bottles. You need your travel set and your sling. I got a wonderful sling yesterday. It is adorable, and it will put a baby right to sleep."

Chimes in a guest to People, "Jamie Lynn opened every gift. We all sat in a circle and she opened gifts and thanked every person. It was just a good old-fashioned baby shower."

As for names, Jamie Lynn says she and Casey, who will start planning their wedding once "things settle down," could use a little help.

"We want it to be something special," she explains. "That's something we haven't figured out yet, but I'm thinking hard. I'm working on it. No one has given me any suggestions. I wish they would!"

(Here's a suggestion: Avoid anything fruit-related or a moniker that will get your child, who's already going to be a target, mercilessly teased on the playground.)

The former "Zoey 101" star also acknowledges that getting back to work on the small screen isn't on her to-do list right now.

"I am so focused on the baby that hasn't even occurred to me. You never know what may happen a year from now," figures Jamie Lynn. "There is the possibility I'll go back, but right now, I just want to be a good mom. More than anything, I just want this baby to have a normal life."

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