The mom-of-three took to Instagram with a sweet post on Sunday, calling their three children -- Violet, Saraphina and Samuel -- 'lucky' to have a dad like Affleck.

The action thriller is out Sept. 7.

ET has an exclusive look at how Garner got her toned and sculpted arms for the new movie, which hits theaters on Sept. 7.

The 46-year-old mom-of-three opened up about finding out she was pregnant for the first time with now 12-year-old daughter, Violet, while co-hosting the Mother's Day-themed episode of 'The Ellen DeGeneres Show.'