The couple had been frantically searching for Alaina since the early morning hours in the wake of the deadly shooting.
"Our hearts are broken," the couple said in a statement. "We just learned that our niece Alaina was one of the victims of last night's shooting at Borderline bar in Thousand Oaks."
"Alaina was an incredible young woman with so much life ahead of her and we are devastated that her life was cut short in this manner. We thank everyone for your prayers and ask for privacy at this time," the statement read.
Mowry-Housley later posted a heartbreaking tribute to her niece on Instagram.
"Alaina. My sweet, sweet Alaina. My heart breaks. I'm still in disbelief. It's not fair how you were taken and how soon you were taken from us," Mowry-Housley wrote.
"I was blessed to know you ever since you were 5. You stole my heart. I will miss our inside jokes, us serenading at the piano. Thank you for being patient with me learning how to braid your hair, and I will never forget our duet singing the national anthem at Napa's soccer game. I love you. I love you. I love you. You are gonna make one gorgeous angel. My heart and prayers are with every victim of this tragedy."
Actress Tia Mowry echoed her sister's sentiments, posting on Twitter that the family is heartbroken.
Our sweet Alaina Housely is gone. We love you. We are devastated.— Tia Mowry (@TiaMowry) November 8, 2018
A freshman resident adviser took a group of women to Borderline Bar & Grill for a fun night out, but Alaina Housley did not return.
A Pepperdine University suitemate of Alaina Housley went on Twitter to say her friend was missing and offered a description of what she was wearing. Mowry-Housley responded by identifying herself as Housley's aunt and sought to contact the suitemate directly.
Alaina Housley was a freshman, but in her short time at Pepperdine, friends talked about what a joy she was to the campus.
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Mowry-Housley's husband, former Fox News correspondent Adam Housley, also took to Twitter to ask: "Please pray if you believe....pray."
There were a total of 16 Pepperdine students at the bar during the shooting. Two other women were taken to a local hospital to be treated for injuries, but have since been released.
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