By peoplestaff225
Updated January 29, 2008 12:42 AM

Although she made a remark to the contrary last week — perhaps to protect her privacy or because they hadn’t yet made a final decision — Jessica Alba revealed on the Late Show with David Letterman this evening that she and fiancé Cash Warren do know the sex of their baby — but they aren’t sharing!

While being teased by Dave for being ‘just a kid’ herself, the 26-year old actress also narrowed down the due date mystery a bit — looks like the ‘late spring’ part of the announcement means May, as Jessica mentioned the baby will arrive after her April 28th birthday.

Expounding a bit on her earlier ‘all day sickness’ comments, Jessica revealed,

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