Vanessa Lachey is "still evolving as a woman and a mother."
The 34-year-old star, who has two-year-old son Camden and three-month-old daughter Brooklyn with husband Nick Lachey, admits she can't believe she has two children.
The brunette beauty said: "It's still very surreal to me that I'm a mother of two. I am loving every day of it. It's not really hit me yet. I'm still evolving as a woman and a mother, and so what I'm learning from her, and my son, and my husband is an every day journey."
Asked how they came up with their daughter's name, Vanessa said: "Well we love New York. We were actually here in New York and we thought Brooklyn Lachey sounds a little better than SoHo Lachey or East River Lachey or The Bronx Lachey."
The former Miss Teen USA winner was tempted to "go back and hug" a stranger's crying baby on her flight after flying to New York City without her children this week.
She told the 'TODAY' show: "It was the first time travelling with neither of my children. You just have this empathy. You just miss them."
Vanessa is currently working with the organisation March of Dimes, which works to end premature birth, birth defects and infant mortality, and was inspired to get involved because she was terrified of giving birth prematurely.
She said: "When you're pregnant, the one fear you have is any day now, any day now. It's just a terrifying thing."