The former Lizzie McGuire star, who is mum to toddler son Luca, posed for a sultry selfie in her bathroom mirror on Sunday, 15 March.
Looking as if she'd just been in a swimming pool, the wet-haired starlet uploaded the shot to Instagram with the caption: "Hey mums. We still got it. Love your bod."
Hilary, 27, gave birth to son Luca Cruz Comrie in March 2012.
The 'Come Clean' singer is frequently seen leaving the gym in Los Angeles but has always been very vocal about the fact she won't bow to the pressure of being a certain weight.
She told Health.com last year: "Oh my God, everyone was so hard on me because it took me a year and a half to get my body back…
"This is the body that I have. I have a very athletic build, and I am so proud of what my body has done for me. I had the best, healthiest, strongest pregnancy. And I feel good about myself. But I feel like I'm always in a 5-pound battle, because being 5 feet 2, everything is going to show on me."
Hilary said she lost her baby weight through exercises including boxing and running up hills.
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