We spotted Jessica Simpson and her fiance Eric Johnson going to The Ivy in Santa Monica, Calif., for a special Valentine's Day lunch on Thursday.

The pregnant singer-turned-reality TV star wore tight black pants, a fitted black blouse that showed off her curves, high heels and a pink jacket.

Simpson and Johnson are reportedly in the process of buying Sharon and Ozzy Osbourne's former mansion in Hidden Hills for $13 million. The couple is also planning to exchange vows on the lawn, according to In Touch magazine. They haven't set a date yet.

The singer is expecting a boy later this year. She gave birth to daughter Maxwell in May 2012.

In addition to raising a growing family, Simpson is working on a sitcom about her life. The busy mom is teaming up with the executives behind her reality series Fashion Star for the upcoming series.

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