Johnny Depp Baby Bombshell

Johnny Depp and Amber Heard

There’s a startling baby secret behind Johnny Depp’s quickie engagement to Amber Heard!

A source tells The ENQUIRER the “Pirates of the Caribbean” star’s ailing mother, Betty Sue Palmer, is desperate to see her boy married and with a new baby on the way ASAP – and Johnny will do whatever it takes to make his mom happy.

Betty, 79, suffers from severe respiratory problems, and Johnny is fearful about how much longer he’ll have with her, reveals an insider.

“Betty is hoping against hope to become a grand- mother again,” said a source. “She told a pal that her dream is to hold Johnny and Amber’s baby in her arms. After that, she can leave this world a happy woman.”

Mama’s boy Johnny, 50, is in a mad dash to get Amber, 27, to the altar as soon as this summer, but the wedding whirlwind seems to be making her nervous. Amber was photographed sitting in a car looking extremely distressed on March 13, just a day before she and Johnny held a lavish engagement party with their friends in Hollywood.

“She truly loves Johnny and wants to be married and have a baby,” the insider continued. “It’s just that it’s all happening so fast, and she’s getting the jitters.”

A source pointed out that just two years ago, Johnny had a serious scare with his mother’s health. In July 2012, Betty was rushed to L.A.’s Cedars-Sinai Medical Center and reportedly was admitted to the facility’s respiratory ICU. Johnny kept a bedside vigil until she recovered, and since then, Betty has been spotted out using an oxygen tank. 

But the apparatus was nowhere in sight at Johnny and Amber’s March 14 engagement bash at the Carondelet house in Los Angeles.

“Amber was overcome with emotion with all the love and support from Betty and for her stamp of approval on their marriage,” said the source. “After that, Amber’s jitters melted away.” 

Johnny and Amber met on the set of “The rum Diary” in 2009 but didn’t take their relationship public until last year. Johnny has two children – Lily rose, 14, and Jack, 11 – with his former partner of 14 years, French actress Vanessa Paradis.

The lovebirds are now talking about having their wedding close to home in California, rather than opting for an exotic island location, as has been speculated. The source noted: “That trek would be too much for Johnny’s mom.”