Although he is behind bars, the presence of Scott Peterson loomed over Amber Frey’s wedding as his blonde former lover exchanged vows with her prison guard fiance. “Scott’s name was never mentioned — but it was impossible to forget him,” a pal told The ENQUIRER.

Amber, 31, and handsome 37-year-old Bob Hernandez became husband and wife as the sun set over Lake Tahoe on July 5.

Scott was far away, on San Quentin’s death row, where he faces execution for the murders of his wife Laci and unborn son Conner. But he learned about her betrothal as fast as the prison grapevine could alert him to The ENQUIRER’S exclusive story breaking the happy news.

“And the other prisoners didn’t let him forget it,” said an insider.

New hubby Bob also got a quick family introduction to Scott’s ghost. Amber’s dad Ron Frey told us: “Bobby came to me out of respect and told me he wanted to marry Amber.

“I told him: ‘Only two men have been this interested in marrying my daughter — and one of them killed his wife to be with her.’ To his credit, he didn’t bat an eyelid.”