WATCH: Pre-school teacher offers to donate kidney to save little girl's life

(FOX NEWS)- A touching video shows a mother learning that her dying daughter's preschool teacher will donate a kidney to the little girl.

Dena Carreyn, of Madison, Wisconsin, found out last year that her four-year-old daughter, Lyla, has a rare autoimmune-related vasculitis known as Microscopic Polyangiitis (or MPA), which causes damaging kidney failure.

When it became clear that Lyla would need a new kidney, her family started a nationwide donor search this summer.

Earlier this month, Dena received the amazing news that Lyla's preschool teacher, Beth Battista, was a perfect match, and would be donating her kidney.

Dena posted the emotional video on Facebook, showing her being given a box by Battista and other school staff. When she opens it, she sees a note that reads: "I may just be her teacher now, but soon a little piece of me will be with Lyla forever. I'm Lyla's kidney donor."

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