There’s some good news for the Arquette family at last!

David’s big sister, Rosanna is planning a wedding after her investment banker boyfriend Todd Morgan proposed last week, RadarOnline.com can exclusively reveal.

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“Rosanna was kind of taken aback but absolutely thrilled when Todd proposed,” a source close to the situation tells RadarOnline.com. “She’s completely in love and had no hesitation in accepting.

“She didn’t think she would ever get married again and was happy with the way things were between her and Todd. But Rosanna is, at the heart of it, a real romantic and she’s willing to give marriage another go.