"(Jessica would) love nothing more than to get married before Ashlee," a source revealed to Star. "It upsets her that her little sister will be married and she won’t. She gets jealous when Ash gets more attention."

That’s where Jessica’s six-month romance with Dallas Cowboys quarterback Tony Romo comes in. "She’s been showing him rings in magazines," the insider said. "She tells him what she likes, and she does it right in front of his friends, too, so it’s really awkward."

Awkward or not, Jess plans to keep up the pressure. "She been joking to friends that she should take Tony to Vegas, get him drunk and drag him to the Little White Wedding Chapel."

All joking aside, the Star source claimed that if Tony doesn’t pop the question soon, Jess may just make the proposal herself. "She knows he can’t say no to her."