Jake Gyllenhaal Opens Up About His Desire to Be a Father: 'It Is Definitely a Dream of Mine'

The 'Southpaw' star opened up about his paternal instincts.

In the upcoming boxing drama Southpaw, Jake Gyllenhaal plays star fighter Billy Hope who, after a tragic downfall, fights to redeem himself in the eyes of the world and his especially his daughter.

While Gyllenhaal himself doesn't have any children, the 34-year-old Oscar-nominated star says that he hopes to be a father one day.

WATCH: Why Jake Gyllenhaal Loves the Challenge of Drastically Changing His Body For Films

Speaking with ET's Kevin Frazier, Gyllenhaal opened up about the paternal instinct that informed his Southpaw character, explaining, "I am not a father yet, but it is definitely a dream of mine, should I be lucky to have that to happen."

Gyllenhaal added that the actress who plays his young daughter in the film, Oona Laurence, made him even more excited about the idea of being a dad.

"I have nieces who I love deeply and I have children in my life I love deeply, but when I meet Oona for the first time, I just fell for her," Gyllenhaal shared. "Your heart opens up to her."

MORE: 13 Fantastic Fictional Fathers From Film

The actor said that his young co-star actually helped him develop and guide his character and his performance.

"When I started acting with her too, she was the one who was guiding me. We improved a lot, and she would make choices, I would just follow her in an improv, and that's the dynamic," Gyllenhaal recounted.

Check out the video to hear more from the celebrated star about his super-talented co-star, and why he wants to be a dad.

WATCH: See How Jake Gyllenhaal Got Super Buff for 'Southpaw'

Southpaw hits theaters July 24.

Gyllenhaal had to shed a lot of weight and put on tons of muscle for his explosive role in the gritty boxing drama. Check out the video to see how the star got in crazy shape for Southpaw.