Jim Carrey To Be A Grandfather!

It's no joke! Jim Carrey's rocker daughter Jane Carrey is expecting her first baby and her dad is thrilled, RadarOnline.com reports.

"I am very excited," Jim, 47, said. "Jane is going to be a great mom."

Jane, 21, a rockstar, fronts her group the Jane Carrey Band. The babydaddy is Jane's long-time boyfriend Alex Santana, who goes by the stage name "Nitro" with his own rock band, Blood Money

"Jane is ecstatic," a source says. "She and Alex are now engaged and are thrilled at becoming parents."

Jane's mother is Melissa Womer, Jim's first wife. Jim and Jenny McCarthy have been together for several years.

Congratulations to the Carrey-Santana family!