'Teen Mom', Jenelle Evans returns to her hotel after spending the day shopping in New York City November 4, 2011 Credit: INFphoto.com

If Jenelle Evans has her way, she'll have some perky new friends on the next season of Teen Mom 2.

As Us Weekly previously reported, the 20-year-old single mother is planning to go under the knife for a breast augmentation. "Jenelle is serious about the breast implants, and even though a lot of people are telling her she doesn't need them, she's convinced," a source close to Evans explains. "She wants to go a 'size or two' higher."

The North Carolina college student "has been bragging about meeting with a plastic surgeon," another insider tells the new issue of Us Weekly (out Friday). Evans' boyfriend of two months, Gary Head, 22, is also "egging her on," the insider adds.

Evans, mom to son Jace, 2, is ready for a change in more ways than one. "She has done a 180 and matured," the insider says of the MTV reality star, who was sentenced last fall to one year of probation for fighting.

Echoes the Evans pal: "This probation has taken a lot out of her."