Hilary Duff pilates pregnant sunglasses blonde singer

Is that you, Mary-Kate?

Hilary Duff looked like she could have been one of the Olsen twins with her long wavy blonde locks and '60s-style circlular sunglasses as she left her much beloved pilates class early Tuesday morning.

In fact, she was so excited to keep up with her prenatal pilates routine that she even took to Twitter to rave about her trainer, Viveca Jensen. Hil, 23, rounded out her super comfy look with a gray and white button-down cardigan, red t-shirt, black straight leg jeans and gray Toms shoes.

Even though Hil is really open with her fans, a few of them had some backlash for her after a simple Tweet this morning. Just before class, the former Lizzie McGuire star wrote, "Just laying in bed with mike&some of the pups.Enjoying how quite it is.Don't think it will last long with this little bambino on the way:)"

But Tweeters jumped on the quite/quiet slip-up. Hil responded, "Ha!and yes I did mean quiet!Sheesh cut some slack you crazy people I just woke up..a prego brain is allowed a few slip ups no??"

Team Hilary!