10/07/2007 at 04:00 PM EDT
A shopping spree in West Hollywood is nothing unusual for Christina Aguilera
. But this excursion early Saturday evening was a first for the singer.
With her husband Jordan Bratman, her mother-in-law and her sister-in-law in tow, Aguilera spent two hours picking out items for her baby registry at the posh Robertson Boulevard boutique Bel Bambini.
"She looked beautiful," says store sales employee Crysta Smith about the singer, who wore a long black skirt and a cotton jacket. "She had a little bump. She said she was so excited [to have a baby]."
Aguilera, who has never officially confirmed
her pregnancy, told the staff that she was expecting – and revealed the gender of her baby, but asked to keep it private.
With the help of her in-laws, the couple picked out a selection of items for her upcoming baby shower, including blankets, diaper bags, bottles and clothing.
"They registered for all the accessories," says Smith. "They were both picking out things together."
This will be the first child for the couple, who married on Nov. 19, 2005, in a lavish three-day affair in California's Napa Valley.
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