Ken Baumann Ken Baumann

Getting married just because you're expecting a baby from a one-night stand is not exactly the best reason to say "I do." Or is it?

Last week, Ben balked at his father's suggestion to wed Adrian (Francia Raisa) on The Secret Life of the American Teenager (Monday at 8/7c on ABC Family). The teen, however, will have a change of heart on Monday's episode when the two go in for Adrian's first sonogram.

"He definitely is not decided for sure," Ken Baumann, who plays Ben, tells "I think [seeing a sonogram is] an overwhelming experience for anyone, especially for a teenager. It's times like that where he realizes the gravity of the situation. Ben's kind of a neurotic guy. He's always going to have the 'grass is always greener' portion of his brain ticking."

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