Chris Sullivan Says He's Running on 'Adrenaline and Pure Joy' After Welcoming First Child (Exclusive)

chris sullivan in this is us portrait
Maarten de Boer/NBC/NBCUniversal via Getty Images

ET spoke with the 'This Is Us' star about his new son, new song and more!

It's an exciting time for Chris Sullivan, who became a dad for the first time amid quarantine. The This Is Us star and his wife, Rachel Reichard, welcomed a baby boy named Bear Maxwell this week -- and as he told ET's Keltie Knight, he's running on "adrenaline and pure joy."

While promoting his new song, "Divided," Sullivan shared that he and his wife have "gotten into a pretty good rhythm of getting each other to sleep and rest. And then we've got a little bit of help here at home...I'm still running on mostly adrenaline. Adrenaline and pure joy."

Sullivan added that, "in a lot of ways," quarantine was the "perfect time" for them to have a baby.

"We've been at home for the last four months and we've had a lot of time together," he noted, explaining that while he and his wife have been married for 10 years, "in the last four months, we've gotten to know each other in ways that are deeper and more connected than ever." They also had extra time to get the house ready for Bear's arrival. "We just felt very prepared and now there is no pressure to go anywhere. There is no pressure to do anything. I don't have to go back to work anytime soon."

"For all of the struggle that goes along with these times right now, that's a little bit of a blessing for the two of us," he expressed. "We're just resting and relaxing and really enjoying it."

As for how they came up with the name Bear, the actor explained that while his wife was pregnant she would have a recurring dream in which she was "visited by this polar bear -- and she doesn't really have recurring dreams a lot."

"It turns out that the bear is a symbol of awakening joy, and when we were thinking of names, it just came to her one day," he recalled. "She's like, 'What about Bear?' And I said, 'Oh, like your dream?' And she went, 'That's right, the dream.' And that was it. There were no other options."

Sullivan also praised Rachel, sharing that he was put in the "driver's seat" by the doctor and helped deliver their baby.

"I cannot tell you, to watch my wife labor for almost 20 hours and to watch her deliver this child, there's nothing else like it," he fawned. "It was so primal and powerful and intentional and she just, like, transformed before my eyes. I mean, I already love this woman so much and she's a warrior. It's incredible. Nothing compares to it!"

The actor's This Is Us family has already met little Bear, he shared. Sullivan also gave an update on the upcoming season.

"We had a family Zoom chat last night and I just received [the scripts for] episodes one and two," he revealed. "I, of course, have had no time to read them, but the rest of the cast says that they are off the charts. So I can't wait to read them!"

"[Creator] Dan [Fogelman] has been running the writers' room and trying to figure out how we're all gonna get back to work," he continued. "The writers have a good head start on all these stories and, yeah, it's gonna be a crazy season one way or the other!"

As far as what the next season will touch on, while he hasn't read the scripts, Sullivan said he knows the writers on the show have a "way of tapping into culture and into the average experience of people in this country in a way that no other group of people does."

"That's why people connect with our show, that's why they tune in, that's why they keep coming back," he noted. "So I have no doubt that our writers will, in some way, connect at least the emotional themes of what's going on in the world into our show, but again I gotta read one and two to figure out where we start."

As for his other "baby," his latest EDM single "Divided" with producer Shane Patterson, the former Broadway star said, "I have done music my whole life…I was a little scared. I was a little nervous to jump into an arena I haven't been in before. We recorded the sound and he mixed it and produced it, and it sounds awesome!"

The song's message is a poignant one right now, Sullivan expressed. "'Divided' is a word that can be used in all kinds of ways, whether it be socially, physically, mentally [or] politically. One of the reasons I agreed to do this song is it spoke to me."

"Quarantine has been, for a lot of people, a taxation on their emotional and mental state," he added. "The song is a lot about that feeling, like two different people feeling that push and pull of whether it's depression or anxiety or joy or like right now, I am divided between extreme joy and extreme exhaustion."

"It's just a banger," Sullivan said. "It's got a great beat and you can crank it up and just really connect with what Shane was trying to say."