A source close to Kristen told the magazine, "She asked one of her friends to buy the test because she was worried about someone seeing her at the drug store...She's very nervous about the whole situation."
The source added, "She started to suspect she might be expecting when she realized she hadn't had her period."
"When she worked out she was late, she obviously started to thinking that she could be pregnant," says a pal. "And because of the timing, she thinks Rob could be the father."
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