Sarah Palin is a grandmother.

Daughter Bristol, 18, gave birth to a bouncing baby boy on Saturday, People Magazine is reporting. The healthy 7 lb., 7 oz. baby is named Tripp Easton Mitchell Johnston. He got his surname from hockey dad Levi Johnston, who has been dating Bristol for three years.

"We think it’s wonderful," Colleen Jones, the sister of Bristol’s grandmother Sally Heath, told People. "The baby is fine and Bristol is doing well. Everyone is excited."

News of Bristol Palin’s pregnancy broke after Sen. John McCain chose Palin as his running mate in the White House race. Johnston, also 18, was soon seen on the campaign trail with the Palins. Johnson said in October that he plans to marry his high-school sweetheart next year.

Palin’s office did not return phone messages Monday.

The Alaska governor, who has a newborn herself, told Access Hollywood last month that she would support her daughter.

"Bristol is a very strong young woman and she’s going to be just fine and a wonderful mom," Palin said.

"Bristol and I and the rest of the family know this is a team effort. And to be thrust like that into a spotlight on a national scene was perhaps an unfair shot to be taken. But really, if we don’t have thick enough skin at this time, as candidates, and I consider our whole family – this is a candidacy for all of us, we shouldn’t even be running for office. But we know it’s all going to be worth it in the end."