duffsharpened020813.jpg That smile brightens our day!

Hilary Duff looked adorable in a hot pink sweater and matching lipstick as she took her son Luca for a playdate with model Molly Sims and her son Brooks yesterday, and it looks like the Lizzie Maguire star is an expert at juggling her little wriggle worm!

The actress/singer and the Sports Illustrated stunner both take their tots to the same infant music class. The little ones are bound to be future Hollywood besties!

With all the play time, Hil still hasn't forgotten about work, though!

"3 meetings today all on opposite sides of town! Vroom vroom living out of my car today..." she tweeted just the other day.

We're dying to know what projects Miss Duff has up her colorful sleeve!