The actress stops by "The Ellen DeGeneres Show" on Monday, where she opens up about her new green 'do and her adorable three-year-old son, Luca.
Check out the sneak peek above to see what 27-year-old's son thinks about her teal tresses!
"I've never done anything like this and I was just in Cabo with my son and I was staring at the ocean and I was like I want that on my head. So this happened," Duff tells Ellen in the clip.
Hilary's little boy also sounds like he's a fan of her new look, too. "Here's the thing. Luca is very particular about how he likes my hair. There's absolutely no buns on my head, no ponytails. I'll have a ponytail and he's like um, hair down mom. Hair down please. I'm like 'at least he knows what he likes,'" she confesses.
"He saw it and he's like 'is your hair's green mom?' and I'm like 'that's right it's green,' he's like 'wow,'" the "Lizzie McGuire" alum adds.
Hilary also opens up about making headlines for her hot bod -- where Duff looked a-m-a-z-i-n-g in a bikini pic she shared on Instagram earlier this month (below).
"You now what, I've never done anything like that before. My Instagram page is pretty tame. And I had spent all weekend in a bikini and I was feeling pretty good. I'm just like everyone else. Usually I'm not feeling so good. I [have a] love hate relationship with my body and I don't know, I was on a trip with my son and it's been 3 years since I had him. I'm like, I'm just so proud of my body and what it's done for me," she tells Ellen. "It gave me the most beautiful little boy and I feel strong and powerful and I wanted to inspire other women."
What do you think about Hilary's candid comments? Tell toofab below and make sure to check out the second video to see what Duff had to say about all of her tattoos!