"I think if everything else she does in her life is an indication of what a great mom she'll make, she's going to be the best mom in the world," Gerwig told PEOPLE Saturday at the Film Independent's Spirit Awards of her No Strings Attached costar.
"She's a smart lady," adds the Greenberg actresses, who had the misfortune of being Portman's competition in the best lead actress category at the Spirit Awards. (Portman took home the prize.)
The two actresses have kept in touch since wrapping No Strings Attached and have spent time together in New York, where Gerwig lives and Portman has been residing with finacé Benjamin Millepied.
"She's a lovely girl to pal around with," says Gerwig. "It's been really great to know her, and she's so up for really fancy, cultural things. It's always museums and stuff."
Of working with Portman on No Strings Attached, Gerwig gushed, "It made me feel like I was really in the movies."
And while the independent film star likely knew her odds of coming out on top against Portman in the best actress category were slim, she was nonetheless "thrilled" with her nomination.
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