Hendricks, who plays Joan Holloway on the Emmy Award-winning TV series, is working with the children's charity and the Latisse Wishes Challenge to help them reach their fundraising goal of $2 million (£1.25 million) - all of which will be used to spread joy to critically ill youngsters in the U.S.
She tells SELF Magazine, ""Despite coping with such serious and adult things, they just want the chance to play and be kids. These children have such strength... We want to grant a wish for every Make-A-Wish chapter in the country.""
And for Hendricks, the mission hits close to home because she's seen first-hand how rewarding the organisation's work can be.
She adds, ""Around first grade, a girl in my class wanted to meet actor Erik Estrada, and Make-A-Wish made it happen. It was amazing! I met him myself years later and got to tell him how special it was for her.""