Christina Ficara - All Headline News Staff Reporter

TECUMSEH, NE (AHN) -

Mackenzi Berglund is a 3-year-old toddler who is the average weight of a 13-year-old at 108 pounds, 42 inches tall.

Reports coming out of Nebraska have revealed that the child has gone from a children's clothing size 6 to a 16 in just one year.

Doctors at the Nebraska Medical Center and Children's Hospital in Omaha, have yet to provide a firm diagnosis - current focus is on a possible genetic disorder.

Because of her size, Berglund as developed severe sleep apnea, resulting in heart failure.

In addition to her heart strain, walking and balancing are more difficult for her. The extremely rare condition, which has yet to be named, will most likely cause arthritis in her joints before she is 7 years old.

As she matures and is incorporated into a social network with her peers, her emotional well being will also be at stake.

A fund to aid the family, Mackenzi Berglund Benefit Fund, has been set up at Auburn State Bank.