Ashlee Simpson's wedding preparation with Evan Ross of "The Hunger Games: Mockingjay" has just reached a higher gear as the "Pieces of Me" singer has been hitting the gym a lot lately. Meanwhile, Ashlee Simpson's ex Pete Wentz took a stroll with his pregnant girlfriend.

Over the weekend, Ashlee Simpson was spotted going to the gym on an all-black ensemble, reveal.com reported, dismissing the reports that she's expecting a baby and at the same time, getting rid of the extra pounds presumably to fit into her gown.

The date for Ashlee Simpson's wedding with fiancé Evan Ross has already been scheduled but the couple is keeping that private for now.

What Evan Ross was only too willing to share was that her mother, Diana Ross, is very hands-on with the wedding.

"My mom is helping plan my wedding right now," the "Hunger Games: Mockingjay" actor said. "She's involved in all levels of my life."

"Honestly, we could go and get married right now, wherever," he told E! News. "This is the most incredible time I could ever think of in my life and I'm young, but the same time, I've lived a different life than most and I can't think of a happier moment."

Meanwhile, Ashlee Simpson's ex Pete Wentz and his pregnant girlfriend, Meagan Camper, were seen strolling in Encino, California last Tuesday. Showing off her new curves, the 24-year-old model was wearing a Guns N'Roses sweatshirt while the Fall Out Boy bassist was wearing a Mike Tyson sweatshirt.

Pete Wentz and Meagan Camper started dating in 2011 after Pete Wentz and Ashlee Simpson's divorce was finalized.

When he guested on The Wendy Willams Show, Pete Wetnz said that he's still surprised that the model hangs out with him.

"I feel like, 'hot girl pictured with homeless man trying to beg her for change' [when we're out together].' This is like charity work here."

"I feel really lucky. It's really interesting to be in a relationship with someone who's truly my best friend. I talk to her about everything," he added.