Theroux, 42, was spotted by photographers in Manhattan’s West Village Tuesday at the boutique perfumery Aedes de Venusta, where he presumably picked up a gift for the birthday girl.
That night, he attended a party at the Deth Killers store opening elsewhere in the city. “Justin was very sweet,” a rep for the opening tells PEOPLE. “Smiled for pictures, and was friendly to staff in the shop. Took selfies with partygoers alongside Orlando [Bloom].”
Theroux arrived at the bash around 7:30, according to the rep, after spending the day filming his new show, The Leftovers.
“Justin was upbeat and laughing in the shop with Orlando, as he tried on different hats, which he ended up wearing out at the end of the night,” says the rep.
Back in Los Angeles, Aniston was spotted celebrating her birthday with friends at SoHo House Tuesday in West Hollywood.
The star was dressed in jeans, a simple top and a black jacket, and joined her party (which included pal Courteney Cox) in a private room.