OK! Exclusive: Sister Envy! Jessica Simpson Pressuring Eric Johnson For Another Baby After Sis Ashlee Welcomes Daughter

Jealous Jessica! After Ashlee Simpson welcomed an adorable daughter, Jessica Simpson’s maternal instincts went into overdrive and friends say the mom-of-two is so in awe of her sister’s baby, she’s ready for baby number three!

A pal told OKMagazine.com exclusively that Jessica is convincing her husband Eric Johnson to expand their family of four.

“Jessica and Eric always said their family was complete, but she’s really gone crazy over Jagger,” the source said over Ashlee’s baby.

Simpson is currently a mother to Maxwell, 3, and Ace, 2, while Ashlee and husband Evan Ross welcomed Jagger Snow on July 30. The source said Jessica “burst into tears when she first saw her” baby niece.

And while Jessica was the topic of public scrutiny about her weight during and after her pregnancy with Max, she’s ready to put it all on the line again for another bundle of joy.

“After finally going through a really good pregnancy second time around, she’s not put off by doing it again,” the source said.