"Knocked Up" star Seth Rogen has proposed to his longtime girlfriend.

The actor has been dating writer/actress Lauren Miller since 2004. Both are 28.

A source close to the couple tells Life & Style magazine, "He surprised her with the proposal. She'd started giving up hope that he would ever pop the question."

Rogen is sure to be one happy man - he previously stated, "I have a girlfriend who is far prettier than I should have."

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