The 'Bullet Train' actor opened up in a recent profile about his wife and their family.
However, Aaron was apparently hesitant to share too much when it came to his romance with Sam -- which may have something to do with weathering a storm of criticism since the start of their romance due in large part to their 23-year age gap.
"I've probably talked to you more about my kids and Sam than I have with anybody," Aaron said in the interview, when shutting down a line of further questioning about his marriage. "I've got really nothing to hide, and I'm secure in what we have."
"But I'm not going to unlock things that are actually precious to me," he added.
The pair met on the set of the 2009 drama Nowhere Boy, which was Sam's directorial debut, and starred Aaron as a teenage John Lennon. At the time, Aaron was 18 and Sam was 42.
Addressing comments about the nature of their interactions and how they first sparked their romance, Aaron stressed that his love for Sam was nearly instant, and it wasn't colored by the dynamic of their working relationship. "I met Sam as actor and director. I think we're really great at collaborating," he said. "But that's not why I fell in love with her."
The pair went on to tie the knot in 2012, and share two children together -- Wylda, 13 and Romy, 11 -- as well as Sam's daughters -- Angelica, 25, and Jessie, 15 -- whom she shares with ex-husband Jay Jopling.
Aaron opened up about life as a father, and reflected on the joy he gets out of the day-to-day aspects of parenting.
"I enjoy the normality of things, the everyday stuff," he said. "Getting my kids ready in the mornings, taking them to school and activities... That feeds my soul."
Looking back at his own childhood, Aaron said that his vision for his life, when he was young, essentially came to pass.
"[I knew] I was going to have a big family. I knew I was going to be a young father. I knew I was going to have many kids," Aaron shared.
For more on the Bullet Train star, check out the video below.