Sienna Miller may be shy when it comes to talking about her personal life -- including her growing baby bump -- but she looked as happy as can be over the weekend.
The actress and her fiance, Tom Sturridge, were spotted strolling around Portofino, Italy, on Sunday, walking hand-in-hand as they took in the sights before heading to dinner.
Rumors started swirling back in January that Miller and Sturridge are expecting their first child together. The pair began dating after Miller's February 2011 split from actor Jude Law, and shortly after the pregnancy rumors came the engagement rumors, which were fueled when the actress was spotted with a ring on her engagement finger earlier this year.
Miller debuted her baby bump in February at W magazine's "Ever Changing Face of Beauty" exhibit, and later opened up about her pregnancy to Vogue UK.
"I'm in my second trimester, so I'm I-can-talk-about-it pregnant, even though I'm under strict instructions not to say anything as it would completely defeat the point of everything I've tried to achieve in the last eight years," she told the British magazine in its April issue, referring to her goal to keep her private life under the radar.
Check out a photo of Sienna and Tom below:

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Jenna Dewan-Tatum
Jenna and her husband Channing Tatum are expecting their first baby together next year, <a href="http://www.huffingtonpost.com/2012/12/17/jenna-dewan-tatum-pregnant-channing-tatum-first-child_n_2316443.html?1355766274">their reps confirmed</a>. Channing's next title? Sexiest daddy alive.
Jessica Simpson
Jessica announced that <a href="http://www.huffingtonpost.com/2012/12/25/jessica-simpson-pregnant-baby-maxwell-photo_n_2362558.html">she's expecting her second baby</a> on Christmas. She and fiance Eric Johnson have a seven-month-old daughter Maxwell.
Kim Kardashian
The reality star is expecting her first child with boyfriend Kanye West. She confirmed the happy news on Dec. 31, <a href="http://kimkardashian.celebuzz.com/2012/12/31/new-year-new-beginnings-kim-kanye-pregnant-first-child-expecting-baby/">writing on her blog</a>, "It’s true!! Kanye and I are expecting a baby. We feel so blessed and lucky and wish that in addition to both of our families."
Fergie & Josh Duhamel
The couple announced their baby news on Twitter Feb. 18, after weeks of speculation.
Penelope Cruz
The actress is expecting her second child with husband Javier Bardem. The couple already has a 2-year-old son Leo.
Danneel Harris and Jensen Ackles
The former "One Tree Hill" star and the "Supernatural" actor are expecting their first child later this year.
Evan Rachel Wood
The actress is <a href="http://www.huffingtonpost.com/2013/01/11/evan-rachel-wood-pregnant-jamie-bell_n_2456954.html">expecting a baby</a> with her new husband Jamie Bell.
CaCee Cobb & Donald Faison
Jessica Simpson's best friend Cacee Cobb and new husband Donald Faison are expecting their first child together. The couple of six years married in December in the backyard of Faison’s "Scrubs" co-star Zach Braff.
Tracy Morgan
The actor and comedian and his model fiancée Megan Wollover are expecting their first child together early this summer.
Halle Berry
Berry is expecting her first child -- a boy -- with fiance Olivier Martinez. She is already the proud mommy of 5-year-old daughter, Nahla.
Jamie-Lynn Sigler
Sigler and her brand new fiance Cutter Dykstra are expecting their first child together.
Hilaria & Alec Baldwin
The couple announced that <a href="http://celebritybabies.people.com/2013/02/12/alec-baldwin-hilaria-baldwin-pregnant-expecting-baby/">they're expecting their first child</a> together. Alec already has a 17-year-old daughter, Ireland, with ex Kim Basinger.
Kate Middleton
The Duchess of Cambridge is <em>officially</em> expecting her first child with Prince William! The mom-to-be is <a href="http://www.huffingtonpost.com/2012/12/03/hyperemesis-gravidarum-kate-middleton-pregnant_n_2234099.html">suffering from Hyperemesis Gravidarium</a>, a rare maternity condition which brings on severe nausea, vomiting, weight loss, dehydration, lightheadedness and fainting.
Mario Lopez & Courtney Mazza
The newlyweds are expecting their second child, Mario revealed. “I am the happiest father in the world," <a href="http://www.extratv.com/2013/02/19/mario-and-courtney-lopez-expecting-baby-no-2/">he told Extra</a>. "We cannot wait to welcome baby Lopez number two into our lives.”
Mark-Paul Gosselaar
The "Saved by the Bell" star and his wife Catriona McGinn are expecting their first child together this September. Gosselaar is already a dad to two kids -- son Michael, 9, and daughter Ava, 6 -- with ex-wife Lisa Ann Russell.
Jamie Anne and Marshall Allman
"The Killing" star and the "True Blood" actor are expecting twins in the spring of 2013.
Busy Philipps
The "Cougar Town" star is <a href="http://www.huffingtonpost.com/2012/12/10/busy-philipps-pregnant-cougar-town-star-expecting-second-child_n_2272754.html">expecting her second child</a> with husband Marc Silverstein.
Heather Morris
According to Us Weekly, Heather Morris, 26, and longtime beau Taylor Hubbell are expecting their first child.
Ivanka Trump
Trump and her husband Jared Kushner <a href="http://www.huffingtonpost.com/2013/04/11/ivanka-trump-pregnant-second_n_3060630.html?utm_hp_ref=celebrity" target="_blank">are expecting their second child</a> this fall.
Sarah Wright
Wright and her husband Eric Christian Olsen are expecting a baby boy in August, <a href="http://celebritybabies.people.com/2013/04/17/eric-christian-olsen-expecting-son/" target="_blank">People confirms</a>.
Kyla Weber
Vince Vaughn's wife <a href="http://www.huffingtonpost.com/2013/04/27/vince-vaughn-baby-actor-wife_n_3169237.html?utm_hp_ref=celebrity" target="_blank">is expecting the couple's second child</a> in August. The pair already has a daughter Locklyn.
Jaime King
The "Hart of Dixie" star is expecting her first child with husband Kyle Newman.
Rachel Leigh Cook
The "She's All That" star and her husband Daniel Gillies are expecting their first child this fall.
Monica
Monica is expecting her first child with husband Shannon Brown, but she's already mom to sons Rocko, who turns 8 later this month, and Romelo Montez, 5.
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Posted: 05/07/2012 2:42 pm Updated: 05/07/2012 2:42 pm