MINNEAPOLIS (WCCO) -- A 10-year-old boy from Wisconsin just wrote the biggest check of his life.

He donated $20,000 to a children's hospital, and he raised that money in a unique way.

Blake Kroll lives in the Green Bay area.

He said he'd donate $500 to a hospital if he could raise it at an auction for his blue ribbon hog named "Spots."

The paddles for donations went flying!

He raised more than $15,000 from 30 different donors in just 10 minutes.

Then, more checks came in the mail.

Kroll chose the children's hospital because the doctors helped get him healthy a few years back.

The Children's Hospital of Wisconsin plans on putting up a special nameplate to recognize the generous gift.