Spears spent her birthday with her fiancé Casey Aldridge. The couple had dinner at Ruby Tuesday restaurant and then went shopping at Wal-Mart.
A source stated, "They both seemed really happy, both in really good moods. Jamie Lynn had a big smile on her face. It was just the two of them," says the source. "They were like a little adult couple, very low-key."
Spears and Aldridge are expecting their first child together this summer.