07/19/2007 AT 04:00 PM EDT
With more than a year of motherhood under her belt – along with eight months of marriage to Tom Cruise
– Katie Holmes
is clearly coming into her own, and turning heads as one of the most stylish moms of the summer, PEOPLE reports in its new issue.
The transformation has been evident – from her playdate in Berlin's Tiergarten park, chasing daughter Suri in teetering heels and wide-leg Roland Mouret pants – to her stunning surprise appearance the red carpet at this week's New York City premiere of Hairspray.
The 28-year-old star "has a serenity about her," says Callie Khouri, her director on the upcoming bank heist comedy Mad Money
(due in early 2008). "I just think she's in a really happy place. She's obviously in love – with Tom and with her child."
During the film's recent two-month shoot in Shreveport, La., Holmes – joined by doting dad Cruise, 45, and Suri – also proved her skill at every mother's juggling act. "She's very focused when she's at work, then in between setups she'd be very focused on Suri," says Khouri. "She had to be all things to all people. It's a challenge, but she certainly is up for it. She's really good at it."
Still, it's hard to imagine a role that allows Holmes to shine more than motherhood. Suri "is a beautiful little girl, and I feel so honored to be her mom," the actress told PEOPLE earlier this year.
For more on Katie's life as a mom, plus photos of her style transformation and her playdates with Suri, pick up the latest PEOPLE, on newsstands Friday.And check out People.com's own Hot Moms of Summer photo gallery!