The Honest Company founder, who is expecting a baby boy with husband Cash Warren, stepped out for the occasion in a simple black dress featuring a full skirt and bow shoulder ties.
The 36-year-old actress, who is already mom to daughters, Honor, 9, and Haven, 6, pulled the look together with bow-embellished headband, a Lady Dior hand bag and black ankle-strap platform pumps.
Celeb guests at the tea-themed party included designer Rachel Zoe, who was spotted wearing a double-breasted blazer with matching trousers for the occasion, and model-actress Molly Sims.
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