She may be months away from giving birth, but first time mom-to-be Minnie Driver is already bracing for those sleepless nights.

“I’m going to be a very tired mother, I’m sure!” Driver told People at the season-two premiere of The Riches in West Hollywood Sunday.

“No, I’m going to be happy,” she corrected. “I’m going to be a happy mother.”

The 38-year-old has a busy couple of months coming up – she’s releasing her album, Seastories in the U.K. and touring Europe, Hawaii and L.A.

But after that, Drivers says, she’ll be logging plenty of pre-baby R ‘n R. “I’m just going to have the summer to be fat and happy,” she said.

Driver announced her pregnancy last week on The Tonight Show with Jay Leno, joked about baby names with Ellen DeGeneres, and said she is four months along – but has not named the father.

The actress, wearing a black, body-hugging Calvin Klein dress and lavender wrap, came solo to Tuesday’s premiere (her first public event since announcing the pregnancy). During the afterparty at the Pacific Design Center’s Red Seven restaurant she laughed with friends and sipped water while munching on appetizers.

On the red carpet, costar Eddie Izzard told People Driver will be a great mom.

“As long as there is one parent there that is giving love, then the kid is going to do great,” Izzard said. “I think she’ll be a good mom because it needs love.”

Added fellow cast member Todd Stashwick: “She’s got a heart as big as the world. I think that could only [benefit] her children.”

WENN