An Idaho family facing its first Christmas without its matriarch got the surprise of the season when they opened their front door to a Christmas caroling flash mob.

More than 100 Rexburg, Idaho, residents and Brigham Young University-Idaho students came together to surprise the family in its front yard Friday night.

Anna Gundert, 34, unexpectedly died of unknown causes while working on July 31, according to the Rexburg Standard Journal. She was survived by her husband, Jason Gundert, and four children, including two 9-year-old twin girls and a 5-year-old boy, EastIdahoNews.com reported.

"The main goal is just to make them smile, to make the family happy and to have them take away something that ... can ... help them through this tough time," organizer and BYU-Idaho student Chris White told EastIdahoNews.com.

White organized the event on Facebook after learning about the family's sudden loss. Under a video of the event posted to YouTube, White said he "felt deeply for this family, who I hadn't ever met, and I wanted to do something for them."

Anna Gundert's sister, Patti Eaton, told EastIdahoNews.com she saw the event online and planned to attend before realizing it was for her sister's family.

"I still can't believe what strangers are willing to do to help my whole family after the sudden death of my baby sister this summer," Eaton wrote in a Facebook post on the night of the flash mob. "I am still in awe, but the kindness and service of strangers, that's the only gift I want[ed] and needed this Christmas."

Carolers sang for the Gundert family, dancers danced, a man beat-boxed and two drummers played during a rendition of "Little Drummer Boy." After the performance, community members presented the family with wrapped presents.

"I felt my mom's spirit," Anna Gundert's 9-year-old daughter Lisette told EastIdahoNews.com.