Bristol Palin and Levi Johnston

In one year, Alaska Gov. Sarah Palin became a new mom, a vice presidential candidate and now a grandmother.

Her daughter, 18-year-old Bristol Palin, gave birth to Tripp Easton Mitchell Johnston on Sunday, People reports.

"The baby is fine and Bristol is doing well," said Colleen Jones, the sister of Bristol's grandmother.

The governor's office said it would not release information because it considers the baby's birth a private family matter

Bristol Palin's boyfriend of three years, Levi Johnston, is the father. A former hockey player at Wasilla High School in Alaska, Johnston is currently studying to become an electrician. When the teenager's pregnancy was revealed during the presidential campaign, Palin's camp announced that Bristol Palin and Johnston would get married.

Sarah Palin and her husband, Todd, have five children ranging in age from 19 to 7 months.

Bristol Palin, who is the second-oldest, is earning her high school diploma through correspondence courses.