Brit to Jamie Lynn: You're a Hot Mama 2 B

TMZ has learned Britney Spears just spent $500 on a gift basket for her newly pregnant unwed teen sister Jamie Lynn. Hey, sis, you gone have a booboo too!

We're told Brit called up West Hollywood celeb baby emporium Petit Tresor late Wednesday afternoon and ordered Jamie Lynn a Tuni & G tank top with the words "Hot Mama 2 B" on it, along with a bunch of all white items including a blanket, a stuffed elephant with a white satin bow, onesies, socks and sneakers. According to our sources, the note attached read: "Dear J.L., We love you! Brit, Sean and Jayden." Auntie Brit luvs y'all!

Now that she's pregnant and famous, Jamie Lynn really is following in her big sister's footsteps. Marriages, divorces, panty flashin', rehab, head shaving and custody battles to follow!