While her big sister Britney is basking in the warm glow of helping How I Met Your Mother garner its highest ratings ever with her appearance on the show Monday, Jamie Lynn Spears may be working on an old-fashioned shotgun wedding.

People says the knocked-up 16-year-old has been sporting a new rock provided by 18-year-old baby's daddy Casey Aldridge.

"She's got an engagement ring," a source says. "She's been showing it up, talking about it."

Of course, the source doesn't mention the stone in the ring is bright red, the size of a golf ball and tastes like black cherry, but we digress. Really, it's awesome to see another teen pregnancy overshadowed by doomed nuptials.

[Photo: Getty Images]