Mary-Kate Olsen has sparked plastic surgery rumors following her recent public appearance in New York City.

Over the years, Mary-Kate has gone through numerous shades of makeup as well as fashion trends to seemingly differentiate herself from her sibling. As usual, she arrived side-by-side with sister Ashley to the 2014 World of Children Awards on Nov. 6. However, the fraternal twins, who used to look quite identical, did not even look similar to each other.

It seemed that Mary-Kate, who barely wore any makeup for the event, had more defined features, especially considering her cheekbones and jaw line.

Dr. Anthony Youn of Youn Plastic Surgery in Detroit claims that the former child actress-turned-fashion mogul might have gone under the knife.

"Mary-Kate's eyebrows look much higher than before, the consequence of a possible endoscopic brown life," he told RadarOnline.

Youn then pointed out that Mary-Kate's "cheeks also look lifted," which is possibly "due to injections of the cheek plumper Voluma."

In addition, the doctor noticed The Row designer's glowing skin at the award ceremony.

"Mary-Kate's skin is also flawless, wrinkle-free and smooth. I've seen skin look this nice after using the high-end Swiss care line Teoxane," he said. "It looks like it's definitely possible."

Another surgeon, Dr. David Cangello, director of plastic surgery at JUVA Skin and Plastic Surgery in New York City, explained the "Two of a Kind" star's alleged dramatic facial alteration.

"Her face looks longer and straighter. Her cheekbone area looks augmented and more linear, as does her jawline," he told Hollywood Life. "Even the lines of the bridge of her nose look straighter and more refined. All of this can be achieved with filler material, and I do feel that the shape of her face has changed over time. Since this is not the case with her twin, it leads me to believe she has probably had some injections with fillers."