The inseparable duo was spotted strolling in the Seaport neighborhood wearing a birthday gift from Philipps: matching “Best Friends” leather jackets.
“Found her. Happy birthday to my better half. I love you, M. You make everything better,” Philipps wrote on Instagram.
But later, the night took a turn when Philipps landed in the hospital with terrible pains in her left side, which she said was determined to be caused by ovarian torsion.
“I had a crazy excruciating pain in my lower right side and after a long time at Mass Gen, it was determined my ovary had flipped over — it’s called torsion,” Busy wrote on Instagram, wearing a “Hysterical Female” sweatshirt.
“Mine flipped back by itself and I’m ok,” she added.
Philipps felt fine earlier in the weekend, and the friends still got plenty of quality time together.
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On Friday, the longtime friends headed to Legal Sea Foods in Park Square on a lunch break, dressed in their costumes from the filming of I Feel Pretty, a comedy starring Amy Schumer that’s directed by Philipps’s husband Marc Silverstein.
Philipps had her bright blonde hair sprayed brown, while Williams wore a sequined black dress and a long blonde wig. Thanks to their costumes, they managed to sneak in incognito.
“Apparently, no one recognized them,” a source at the restaurant told PEOPLE. (Philipps’ brunette look is for a character she plays in the film.)
Filming on I Feel Pretty, in which Schumer plays a woman who hits her head and believes a spell has suddenly made her gorgeous, is finishing up in Boston, and is expected to hit theaters in summer of 2018.