Pretty Little Liars: Who Is On The "A" Team? : Sasha Pieterse Celebrates 21st Birthday in Las Vegas & PLL Cast Sends Bday Wishes

Sasha Pieterse, Alison DiLaurentis on PLL, turned 21 on February 17th! She celebrated her special day at the Marquee Nightclub at The Cosmopolitan in Las Vegas.

A post shared by Sasha Pieterse (@sashapieterse27) on Feb 18, 2017 at 3:35pm PST

Sasha celebrated her birthday with a gorgeous Pretty Little Liars themed cake. The black and gold cake had a red “A” on it.

Sasha Pieterse also went to the nightclub TAO at the Venetian Hotel and did a bit of dancing.

A post shared by Sasha Pieterse (@sashapieterse27) on Feb 19, 2017 at 12:28am PST

And Sasha popped champagne at the Palms Casino Resort.

A post shared by Sasha Pieterse (@sashapieterse27) on Feb 19, 2017 at 4:17pm PST

Sasha Pieterse’s fiancé, Hudson Sheaffer, posted this video of Sasha popping open the champagne bottle. (Hudson proposed to Sasha back in December 2015). He also posted this sweet birthday message to her:

“My love, you are my center, my rock. It's been an incredible journey. I cannot wait to continue in this new chapter of life. The excitement, stress, heartache and the accomplishments. Hand in hand we will take it all on.”

A post shared by Hudson Sheaffer (@hudsonsheaffer27) on Feb 18, 2017 at 12:06am PST

The PLL cast also sent Sasha Pieterse birthday wishes on social media.

Lucy Hale (Aria) posted this adorable photo of the two of them with the message “Happy Bday to my sweet Sashy bear. My life in PLL would never have been the same without you and your supportive, kind soul. I'm excited for all the amazing things in store for you ❤❤❤ @sashapieterse27”.

A post shared by Lucy Hale (@lucyhale) on Feb 17, 2017 at 12:46pm PST

Ashley Benson (Hanna) tweeted “Happy birthday angel ❤❤ love you @SashaaPieterse”.

Happy birthday angel ❤❤ love you @SashaaPieterse pic.twitter.com/HB6tQHi37a
— Ashley Benson (@AshBenzo) February 18, 2017

Shay Mitchell (Emily) posted this Emison photo and wrote “Happy belated Birthday to one of the sweetest, oldest souls I know. There is no one I'd rather run through Rosewood with (literally, #endgame). @sashapieterse27 #jokesonheriatehummusthatday”.