Jessica Alba and Cash Warren aren't raising baby Haven Garner alone, thanks to their three-year-old daughter Honor Marie.

"Haven's so small and can't even pick up her head but she likes to smile. She's adorable," Alba, 30, recently told Us Weekly. "Honor is just the best big sister. I guess that's a pretty great landmark in itself. She's so great with Haven."

Long before she gave birth to Haven in August, Alba began developing The Honest Company to help new moms "find eco-friendly products, like diapers."

Tentatively scheduled to launch in January, Alba's new business has been in development for more than two years. Said Alba: "It's really exciting to have it so close to coming to life!"

"When I was preparing for my first child I started doing research online about how to have a safe home," she explained. "I was completely shocked by how many dangerous chemicals were in so many products that I used."

"We were able to create a safe environment for our family but it was very, very expensive. I understand that not a lot of families have the means to buy all new items and products...but there are a lot of great eco-sites out there are helping people buy safe products."

As a longtime environmental activist, Alba plans to make her daughters' first Christmas together as green as possible.