Hayden Christensen is a very lucky man to have the stunning Rachel Bilson for a girlfriend!

Here are five pictures of the happy couple vacationing in Barbados this week.  I have to say, Rachel Bilson has never looked better, and the pair seems to be having a lot of fun swimming, sunbathing and being in love.  Jealous?

Photos: Fame/Flynet

Here is a recap of just some the celebrity sightings over the weekend! Enjoy!

*Sandra Bullock and son Louis visit a friend in Los Feliz, CA, on Saturday.

*Lady Gaga signs autographs for her little monsters outside the Beacon Theater in NYC.

*A super hot Daniel Craig shopping in the West Village, NY.

*Bar Refaeli shops in NYC on Sunday.

*Jude Law seen at Donmar Warehouse Theatre in London, UK Saturday night.

*Anna Lynne McCord and her creepy older boyfriend Dominic Purcell kick off Women’s Rebuild for the “St. Bernard Project” at Pure Nightclub in Caesars Palace Hotel and Casino in Las Vegas.

*Madonna, boyfriend Brahim, and daughters Lourdes and Mercy James attend Kabbalah services in New York.

*Heidi Klum takes her kids to karate in Brentwood, CA on Saturday.

*Emma Roberts in Los Angeles on Friday.

*Jessica Alba and hubby Cash Warren take Honor to the county fair in Los Angeles on Saturday.

*Adam Sandler takes his daughters Sadie and Sunny to gymnastics in Culver City, CA.

*Rachel Bilson goes shopping at The Grove in Los Angeles on Sunday.

*Topher Grace at Trousdale Friday night.

*Lea Michele hangs out with some friends and visits the Palace of Versailles during the fashion week in Paris, France.

*Rachel Zoe in town for Paris Fashion Week with hubby Rodger Berman and their son, Skyler in Paris, France.

Rachel Bilson and little sister Hattie get all dolled up for an event at Universal Studios in Los Angeles.

Rachel always looks great and her sister is adorable, but let’s take a minute to focus in on Rachel’s shoes.

WOW! I love those shoes. Muy Caliente!

Photos: Fame

Rachel Bilson is currently filming ‘The To Do List’ in which she plays a recent high-school graduate who feels pressure to become more sexually advanced before beginning her college career.

Photos: Fame

Blake Lively, the new face of Chanel, came out in support of it’s Cruise 2012 show in Cannes, France. Amongst the attendees were Blake Lively, Alexa Chung, Rachel Bilson and Vanessa Paradis.

“This is a modern version of sophisticated dressing,” explained Chanel’s creative director Karl Lagerfeld, telling WWD, “Cruise is always about going away…It’s about dressing down these very sumptuous looks, about easy elegance. This is about the women of Cannes, women who mix bathing suits with real pearls and diamonds. After all, you can’t wear fakes into the water.”

Photos: Fame

Rachel Bilson looks great in a bikini! The 29-year-old actress was spotted in two different bikinis in Barbados over the weekend, where she’s vacationing with boyfriend Hayden Christensen.

The couple – who have had a rocky relationship – seem to be back in love. The couple began dating in 2007 after meeting on the set of ‘Jumper’. They reportedly became engaged later that year, but have been on/off since then. They called off their engagement last August.

A representative for Bilson, who starred in The O.C., told People magazine: ‘Yes, the engagement is off.

Work commitments meant the couple had been living separate lives, with Rachel based in Los Angeles, while Hayden was in Canada.

The distance between them was one of the main reasons for the split, a friend said.

‘It just wasn’t working out,’ the friend told People, adding that Bilson was ‘focusing on her career, spending time with her family and just moving forward.’

But three months later in November 2010, it appeared that the couple couldn’t bear to be apart and reportedly started dating again.

And now they appear to be getting completely back on track. They worked together again two years into their relationship in 2009 on one of 11 short films that made up New York, I Love You.

Bilson previously dated Adam Brody, her co-star on The O.C., for three years. Since leaving the show she has moved into film, and was seen earlier this year in Waiting For Forever opposite Tom Sturridge.

Source, Photos: Fame

Rachel Bilson is ready to go in a white long-sleeve tee, denim shorts, flat booty shoes, and a casual black Chanel purse! She makes the most of her day and meets with a couple gal pals in Sherman Oaks, Calif., yesterday (March 10). Rachel pays for her parking meters, grabs lunch, a hug, and stays in good company!

Images via Fame