The 29-year-old actor and Geisendorff are already parents to three-year-old daughter Everleigh Ray, and now they are adding another baby to their brood, reported Us magazine.
Geisendorff was spotted with a baby bump as the family enjoyed a day at the beach in Malibu, California to celebrate America's Independence Day on Wednesday.
"Burlesque" star Gigandet, who appeared as the main villain vampire in the first film of the "Twilight Saga", will soon be seen in "Free Ride" opposite mother-to-be Anna Paquin, later this year.