The Children’s Museum of Southern Minnesota in Mankato learned on Tuesday that it will be receiving a $500,000 gift. The donation comes from the owners of the Dotson Company, Denny and Carole Dotson, and was made through the Mankato Area Foundation. It will be used to fund the construction of a museum feature called “The Back 40,” a self-directed play area with tree stumps, overgrown grass and knolls. The Dotsons are also donating a 1917 Little Giant tractor with parts that were manufactured at the Dotson Foundry. The gift brings the museum’s fundraising total to $3.4-million out of a goal of $4-million.