Country music star Josh Turner is set to be a father for the fourth time.

The singer's wife Jennifer is pregnant with the couple's fourth son, who is due in September (14), and Turner admits he wasn't anticipating adding a sixth member to their family so soon.

He tells People magazine, "It's a welcome surprise. To have four boys is pretty awesome for a father."

Josh and Jennifer are already parents to Hampton, seven, Colby, four, and three-year-old Marion, but have no idea what to expect once another son joins them in a few months.

He says, "People have always told us having three was the hardest. There was this one day a while ago where our three boys were literally driving us crazy. We were ready to pull our hair out and Jennifer was about to scream.

"I looked at her and said, 'Hey, remember everyone always told us that three was the hardest number? We're either having another one or we're giving one away!' I honestly have no idea what it's going to be like. We're just going to take it one day at a time."