03/04/2012 06:14 BST | Updated 03/06/2012 06:12 BST

Levi Johnston, Father Of Sarah Palin's Grandson Tripp, To Be A Dad Again

The father of Sarah Palin's grandson has another baby on the way - with a 20-year-old teacher, TMZ exclusively reports.

Levi Johnston was hurled into the limelight in 2008 after it emerged he was expecting a baby with then vice Presidential candidate Sarah Palin's daughter Bristol.

The pair became engaged shortly before son Tripp's birth, but ended their relationship after a number of very public feuds.

Johnston, an aspiring actor and model, who later posed for Playgirl magazine, is now in a relationship with Sunny Oglesby.

The new baby is reportedly due in around six months time.

While promoting his book, Deer In The Headlights: My Life in Sarah Palin's Crosshairs, the 21-year-old told Huffington Post in September last year he only sees his son around once a month.

The way they were: Johnston with Bristol, and the rest of the Palin clan at the Republican National Convention at the Xcel Energy Center in St. Paul, Minnesota, on 3 September, 2008

He also claimed Bristol, who was 18 when she gave birth, deliberately got pregnant because she was jealous of her mother's pregnancy.

Palin gave birth to her fifth child, a son named Trig in 2008.

Johnston said: "Bristol was on birth control for a long time. She got off it soon after Trig [Sarah Palin's son] was born. I think Trig was a big motivator for her. Her mother just had a child and I think Bristol was really jealous. She was the one who was supposed to have that kid and that's when she got off of [birth control]. We weren't practicing safe sex and she ended up getting pregnant."

For her part, Bristol released her own book Not Afraid Of Life: My Journey So Far, detailing how she lost her virginity to Johnston after getting drunk on a camping trip.

Below, a look back Johnston's time in the limelight with the Palin family, and his famous ex's best (and worst) fashion moments.

Briston Palin's Style Evolution