@milano_alyssa / Instagram 1 / 7
@milano_alyssa / Instagram 1 / 7

Sweet siblings! Alyssa Milano is in mommy heaven right now, following the birth of her daughter Elizabella Dylan Bugliari on Thursday, Sept. 4. The baby girl joins brother Milo, 3, and the proud mom, 41, couldn't be more excited to show off her new family.

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On Saturday, Sept. 6, the "Who's the Boss?" alum, Instagrammed a precious picture of little Elizabella's legs and feet with big brother Milo's arms wrapped around her.

"Milo meets his baby sister for the first time," Milano captioned the touching photo.

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The "Mistresses" star and her hubby David Bugliari were thrilled to expand their family. In the August/September issue of Fit Pregnancy, Milano touched on her decision to have children in her 40s.

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"I loved waiting a long time to be a mom. I'd had my ladies' lunches and my shopping days," she told the magazine. "When Milo finally came, I thought -- this is what I've waited for my entire life. I wish I could sleep more, but it's not like I wish there were other things I could be doing socially or for my own benefit. Because I really feel like he's completed me."