She is actively involved in raising funds and awareness for the Cystic Fibrosis Foundation. Mackenzie's stepsister, Katelyn Salmont, lives with CF and, in 2005, Katelyn underwent a successful double lung-transplant. Both girls will be featured in Teen People's "20 Teens Who Will Change the World". "7th Heaven" (1996) had produced a special episode about Cystic Fibrosis entitled "Back in the Saddle" which featured Katelyn as herself, and Mackenzie and Katelyn rode horses together, as they do at home. In 2005, "7th Heaven" (1996) again brought Katelyn on the show, post-transplant, which gave her a chance to explain about the new life she had been given.

MacKenzie's stepsister, Katelyn Salmont, who suffers from cystic fibrosis, guest-starred as Mackenzie's friend in the "7th Heaven" (1996) episode "Back in the Saddle Again".

Her family has Cherokee Indian roots.

Enjoys reading, skating, swimming and dancing

Mackenzie's family of five includes her Mom, Donna, her step-dad, Randy, her brother Chandler, and her stepsister, Katelyn. Also included in the mix is a menagerie of cats and dogs, chickens, horses and goats.

Mackenzie is a Junior Ambassador for Childhelp Inc., an organization working for and with severely abused children.

Favorite food is sushi.

Contributes her free time to animal charities

Her first passion is horses, it is a family activity.