The 48-year-old DJ revealed that his daughter Jade, 27, is expecting a baby, and he also let slip that her due date is December 29.
Speaking on his BBC Radio 2 breakfast show yesterday (Sunday, June 22), Chris went on to say that he never expected to become a grandfather at such a young age - especially as his youngest son has only just turned two years old.
"My daughter rang to tell me I was going to be a granddad," he told his 9.85 million listeners.
"This now puts me staring straight down the barrel of becoming a granddad at the age of just 48."
Chris Evans' daughter Jade (Credit: Getty)
Chris walked Jade down the aisle at her wedding to car mechanic Callum last September.
Jade is Chris's daughter from his relationship with his former fiancée Alison Ward. Following a brief marriage to Billie Piper, he is now married to his wife Natasha, and the couple have two sons, Noah, five, and two-year-old Eli.
"Noah is going to become an uncle as well as little Eli, who is just two," added Chris. "And Tash is going to be a grandma."
Chris has previously spoken of his and Natasha's struggle to have a second child, and their joy following successful IVF treatment.
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