Luke Grimes Says Starting His 'Little' Family with 6-Week Old Baby Brings Him 'More Joy Than Anything' (Exclusive)

Luke Grimes may have captivated the hearts of viewers worldwide on Yellowstone — but his heart belongs to his "little" family.

The actor and musician, 40, tells PEOPLE that amid his busy schedule wrapping the hit western drama series, on which he plays Kayce Dutton, and working as a professional musician in his personal time, he is still relishing in the "life-changing" aspects of being a father to a 6-week-old son.

Grimes and his wife, Bianca Rodrigues Grimes — with whom he reportedly tied the knot on Nov. 21, 2018 — welcomed their first child together just last month, as shared in a heartwarming Instagram post from Bianca on Oct. 17. "It's just been magical to watch," he says of the experience of becoming a father.

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Nonetheless, he says his trick to keep it all together is to "just try to stay as in the moment as possible" no matter what is going on in his personal and professional life.

"I know some of these things can be kind of overwhelming if you think about 'em all at once," he admits, doubling down that "all I can do is just try to be present."

For Grimes, "family has been a big thing since I was little."

"I [have] a huge immediate family," he shares. "I was the youngest of four. They all got married when I was still very young. So by the time I had nieces and nephews, starting at two years old, there was family everywhere all over the place. It was just sort of that way in Ohio and a Christian home, and so that was always my foundation."

Despite heading to Hollywood to pursue his dreams — and still finding a way "to get along even over long distances" with his loved ones — Grimes says having a family of his own someday remained his "north star" in life.

"I knew one day I wanted to start my own family, and I knew that that was going to be where the real happiness came from. The other stuff was just going to pay the bills," he jokes.

Ultimately, that "other stuff" (Yellowstone included) doesn't compare in Grimes' mind to "having my own family ... my real life little family now is bringing me more joy than anything."

For more on Luke Grimes and Yellowstone, pick up the latest issue of PEOPLE, on newsstands Friday.