Gene Simmons and Shannon Tweed will have their wedding on Saturday at the Beverly Hills Hotel after 28 years together, according to reports.

But will he be faithful?

In a preview of the upcoming season of Gene Simmons' Family Jewels, Tweed, 54, is heard complaining that the 62-year-old KISS rocker doesn't promise to be faithful to me. To which Simmons replied, I will do my best.

Simmons spoke to Entertainment Tonight where he revealed his softer side for his wife-to-be.

I will tell you that when I was standing in front of Shannon, my knees started to buckle, Simmons said. I went down and I thought 'Uh oh, I guess I'm doing it.'

It is time for me to grow up, the rocker added. I'm 62. I've been doing a lot of wacky stuff for an awfully long time - the band, the thing, traveling around the world and all that. There's nobody I've ever loved. There's nobody I've ever said 'I love you' to. I even find it difficult to say 'I love you' to my mother, but I love Shannon with all my heart and all my soul and always will.

Tweed seems pretty happy that after almost 30 years together the man she loves will be marrying her. The Playmate and the rocker have a 22-year-old son Nick and an 18-year-old daughter Sophie.

I'M GOING TO GET MARRIED TODAY!! TO THE MAN I LOVE, she wrote on Twitter on Saturday.

She later added, Everyone said it would rain! It's a perfect day for a white wedding!! has reported that guests of the wedding are asked to donate to the couple's favorite charities instead of providing wedding gifts. The charities reportedly include the Society for the Prevention of Cruelty to Animals, — a non-profit organization that seeks to lessen poverty through micro-loans, the Elizabeth Glaser Pediatric AIDS Foundation, and the Pink Lotus Breast Center.

More wedding details about Simmons and Tweed's wedding will be aired on Gene Simmons Family Jewels, which will be aired on at 9 p.m. ET on A&E on Oct. 4.

Everything from choosing the flowers and wedding dress to the bachelor and bachelorette parties will unfold in the new season, Simmons' spokesperson said in a statement to

Watch the ET interview below and then start the slideshow to look at Simmons and Tweed over the years.