Selena Gomez poked fun at her ex-boyfriend Justin Bieber's new mustache and a source said the laugh helped the Slow Down singer get over being homesick.

Bieber, 19, sat front row at the opening ceremony of New York Fashion Week on Sept. 8 and smiled for the cameras with his new facial feature.

See a photo here of the new look.

Gomez, 21, is currently in Europe on her Stars Dance world. A source told Hollywood Life the singer saw Bieber's mustache in an Instagram photo and thinks it is "hilarious." Seeing her ex-boyfriend trying out the look also helped her miss home a little less.

"She's seen it and she thinks it's hilarious! That gave her a good laugh after being so homesick," Gomez's friend revealed.

Famous Mustaches [PHOTOS]

The former Disney star may be missing her friends and family back home, but she is determined to make the most of her time in Europe.

"It's been a couple weeks but she still wants to enjoy herself in Europe. She has some days off for travel but she is looking to experience some fun times while out there as well," the source added. "It will combat the homesickness feeling if she is having fun."

Bieber flew home to be with his father Jeremy who underwent surgery on Tuesday, evident from a tweet the latter wrote.

The pop singer is working on his 2013 album and his manager said new music will be released in October. Bieber is also filming a new movie that will be a follow-up to his 2011 3-D documentary Justin Bieber: Never Say Never. Production is already underway for the project.

Bieber shot on Sept. 7 an exclusive interview with Jon Chu, the man behind his 2012 film, that will be featured in the upcoming movie.