The newlyweds enjoyed a romantic birthday dinner for Lopez near the Eiffel Tower late Sunday evening, during which Lopez, 53, wore a long black dress, stiletto heels, a pearl necklace and sparkly earrings. Affleck, 49, sported a black suit, white shirt and black shoes.
Around 11 p.m., the couple arrived at the celebrity-loved Le Girafe restaurant, a ’30s-inspired indoor/outdoor seafood eatery with a terrace offering stunning views of the Eiffel Tower.
An observer tells PEOPLE that the Argo actor/director and Marry Me actress were seated at a table closest to the landmark, and had a turquoise balloon attached to their table, which they’d brought with them.
“They were close, very close, to one another the entire time. They embraced one another a lot,” the source adds, saying they seemed very “in love.”
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According to the observer, Affleck took Lopez’s photo around midnight, when she stood up from their table as the tower’s evening lights twinkled.
“Then she released the balloon [and] set it to sail off towards the Tower,” the source says.
Lopez and Affleck wrapped their meal around 12:45 a.m., says the insider, at which time a server brought over a cake with candles.
When the stars arrived back at their hotel around 1:30 a.m., “there were still a few fans out front,” the observer says. “One had brought Jennifer a birthday present … one of those little Eiffel Towers that light up. She was very touched and posed with him,” the source says, adding that Lopez carried the illuminated statue inside.
Earlier on Lopez’s birthday Sunday, the couple mixed couture culture and shopping. In the afternoon, the pair visited the maison Dior on Avenue Montaigne, viewing a new gallery tribute to founding designer Christian Dior. Afterwards, they spent several hours at the refurbished department store Samaritaine, admiring its combination of Art Nouveau design and luxury products
Affleck and Lopez were spotted Saturday evening at the recently opened Plénitude, a skyline restaurant at the hotel Cheval Blanc.
After dinner at the restaurant, the pair stopped for dessert at a Berthillon ice-cream shop on the Île Saint-Louis. Once their night was over, a bouquet of balloons was delivered to the couple’s hotel suite around midnight.
Earlier that day, Lopez and Affleck were seen heading to lunch with their children, before taking a two-hour private tour of the river Seine on Petrus III, a 71-foot teak “gentleman’s yacht” built in the 1950s. They also paid a visit to the Marais district’s Picasso Museum.
The couple was previously seen kissing and cuddling on a park bench for more than two hours on Friday. A source told PEOPLE they were “like two teens … very loving, very attentive.”
Lopez and Affleck later strolled around the city with their kids that same day, walking through the Marais district and Rue des Rosiers, down to the Centre Pompidou. They also enjoyed some vintage shopping and a trip across the Seine to the Musée d’Orsay.