Sica was last seen in Huntsville, Alabama on July 3, 2017. Prior to her disappearance, she had been very active on social media and in regular touch with family and friends, but the social media activity suddenly stopped in June 2017, shortly before her disappearance.

She abruptly moved out of her apartment at The Overlook on Sparkman Drive in July. In August, she emailed her family and said she was in Wyoming and was looking forward to seeing them in January 2018. She has never been heard from again. Sica's family reported her missing in October.