Hilary Duff and Kimberly Stewart showed off their cute mommy styles Saturday, giving their kids a ride on their hips ... hipsters in training!

Hil toted son Luca to pal Jack Osbourne's house -- probably for a playdate with his daughter Pearl. Meanwhile, Kimberly took daughter Delilah to a party in her adorable summer dress. So cute!

Sometimes we totally forget Kimberly Stewart and Benicio Del Toro have a cute little kid together!

Kim and her darling daughter Delilah were spotted at Whole Foods in Beverly Hills on Tuesday, and while we haven't seen dad in a while, he did join the ladies in Puerto Rico last month for Delilah's christening.

Kim and Benicio were never officially together, but the Oscar winner has a "special bond" with the little girl, and Kim previously told Hello! Magazine, "The whole family was at the hospital [when I gave birth] and my mom and Benicio were in the delivery room with me!" Glad he's such a dedicated dad!

It's a girls' day out for Kimberly Stewart and baby Delilah!

The blonde stunner took her darling six-month-old little girl for a cool coffee beverage at a Starbucks in Beverly Glen, on Thursday afternoon.

Rod Stewart's first grandchild looked chic in a mini jean jacket and black tights, while Kim looked rock star-chic in a white tee, black skinny jeans, a cream vest and a blingy cross necklace.

It appears Benicio Del Toro's baby mama has lost all of her baby weight!

Check out our exclusive video of the mommy-daughter duo below!

Kimberly Stewart took 5-month-old daughter Delilah shopping at Beverly Glen mall Saturday ... sans baby daddy Benicio del Toro, of course.

While del Toro has promised to be supportive, it's rare that we've seen the two together with their child. Last April, when Stewart's pregnancy was announced, Benicio's rep said the following in a statement: "Kimberly is pregnant. Benicio is the father and is very supportive. Although they are not a couple, they are looking forward to the arrival of the baby."

That's all well and good, but where's daddy???

Dressed in matching mommy-and-me moccasins, Kimberly Stewart showed off 4-month-old daughter Delilah for the first time in public, as she met Jack Osbourne for a lunch date in Beverly Hills, on Saturday.

No doubt the proud mamma was offering Jack some parenting advice -- he's about to become a daddy for the first time next year!

Osbourne broke the news that his fiancée, Lisa Stelly, is expecting their first child during an interview with Piers Morgan in October.

Jack and Kimberley actually dated from 2003 through 2004, and have remained close friends since their split.

Mischa Barton's fashion sense has come a long way in recent months, and wow, she's looking fit and fabulous.

The former OC actress, wearing black tights and short shorts, hit up the Music Box Theatre in Hollywood to catch Morrissey in concert.

The leggy actress wasn't the only celebrity in attendance. Showing off her slender post-baby bod in an all-black ensemble paired with killer boots, Kimberly Stewart also enjoyed the show and took a night off from watching 3-month-old daughter Delilah. Perhaps the baby was home with daddy Benicio Del Toro?

Girls just wanna have fun!

Baby Delilah is one lucky little girl!

Kimberly Stewart went shopping at French baby boutique Bonpoint on Rodeo drive for her 3-moth-old baby daughter -- Benicio del Toro is the daddy --- and we're betting she already has a wardrobe that rivals Harper Beckham's!

While Stewart is no longer dating the Oscar winner, she tells Hello! mag: "Benicio's very involved; he and Delilah have a very special bond."

Kimberly named her daughter after Tom Jones' 1968 song "Delilah".

Kimberly Stewart said that Benicio del Toro is an active dad, and now we're seeing it in person!

We caught up with the couple and baby daughter Delilah on Tuesday as they took their little one to a doctor's appointment. Delilah was born in August.

Benicio, 44, rocked his usual careless-chic look (and his signature toothpick), while Kimberly, 32, looked boho cute.

So nice to see parents who are both involved!