Glammed up in a bright print dress and yellow heels, the expectant Spears, 17, gassed up her Range Rover on Saturday and headed to Liberty, Miss, where friends threw an early-evening event attended by "30 or 40 people," a source tells PEOPLE.
Unlike the previous girls-only shower attended by big sis Britney Spears in Kentwood, La., on May 3, this event welcomed a few male well-wishers.
While the baby's father, Casey Aldridge, did not put in an appearance, his mom Joyce and sister Ashley were both in attendance. Other than immediate family, "it was a totally different group" from the first event, explained the source. "This one was more [Casey's] family."
After the "really nice" shower, the guests – including the mom-to-be – went out to dinner and then on to a club, the source added.
May will bring even more showers for Jamie Lynn: The Aldridge family is planning to host a bash as well.