Scarlett Johansson - LEAD
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Wednesday's amFAR Gala was packed with stylish and emotional moments, and Scarlett Johansson did her part by donning a power-suit and opening up about personal experiences.

The Ghost in the Shell actress—who wowed at the Cipriani Wall Street event in a black-and-white double-breasted suit and statement Harry Winston earrings—brought her mom Melanie Sloan to the annual charity bash.

As a guest of honor, she addressed the crowd about HIV/AIDS research, awareness, and prevention, and shared anecdotes about how the disease has impacted her family. During a speech, she recalled a friend who transformed their family with his friendship before he passed away in 1993.

"I'd like to acknowledge the more than 37 million people around the world today that are still living and struggling with HIV/AIDS and to dedicate this award to all those that have lost their lives and the lives of their loved ones to this disease," she said. "When I look at this and I think of this night I will always think of Tony. The phrase I was looking for—my mother messaged me last night—was kindred spirit. So thank you all for helping me to honor him."

Scarlett Johansson amfAR - Embed
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During the night, the star also dished about her own experience of being a mother to ET. The actress shares 2-year-old daughter Rose Dorothy with Romain Dauriac—from whom she reportedly split following two years of marriage—and discussed the hardships of having a child and working.

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"I don't profess to know anything about parenting, anything more than anybody else, [but] being a working mom is an incredible challenge, [and] it's an incredible gift."

The 32-year-old admitted, "I think you always feel a little bit of guilt ... If you're at work, you feel like you're missing out on those special moments with your kid. If you're with your kid, you feel like you're not giving enough to your job. It's a balance."

"I have a lot of huge admiration for working moms," Johansson said. "I'm barely, barely holding it together."

—With reporting by Jonathan Borge