The "Church Bells" singer opened up to ET about celebrating son Isaiah's second birthday and what this means for expanding her family with husband Mike Fisher.
"We're on God's good timing or whatever you might call it," she said on Tuesday. "I'm just trying to figure out where life's going to take me next."
Underwood said that Isaiah hasn't been asking for a little brother or sister quite yet. "As a matter of fact," she added, "if a dog climbs up on my lap, I feel like he gets a little jealous of the dog!"
ET sat down with the 32-year-old superstar on Catalina Island in California, where she was in town to perform for military families aboard the Carnival Imagination cruise ship. The American Idol alum delivered a 90-minute set of her biggest hits as part of her work with Operation Homefront.
"It's so important to me because our military does so much for us, and the families are the ones that support the military members," she said. "We had so many incredible families coming out to our concerts last year [on the Storyteller Tour], which is really, really cool. I got to meet some really amazing people."
As Underwood heads back home to Nashville, she's excited to spend time with her own family and work on new music. The seven-time GRAMMY winner recently signed a new deal with Universal Music Group and is already writing for her next album.
"The creative process is an interesting thing," she said. "You never know when it's all just going to come together and then you'll finally be able to be like, 'I'm done! Wow, we've made an album.' So I'm kind of at the beginning stages of that, which is really fun."
Asked what is inspiring her in the writer's room, it all comes back to family.
"I think the people in my life are what really inspires me," she mused. "You know, family, friends, people that I get to meet and I get to hear their stories. I'll probably hear some fan stories and stuff like that today, you know? It's just always cool to be able to incorporate incredible stories about people that you know or people that you meet into your music."
Earlier this week, Underwood shared a sweet family moment with her fans when her hockey-playing hubby passed a game puck to their son from the ice. "It's super special," she gushed.
"I don't know how much of these things he'll remember as he gets older, that's why we try to get lots of pictures," she said. "I don't even know if he realizes a lot of times when he's watching Daddy play that it's his dad. I've taken him down to the ice before and he didn't realize it until [Fisher] was skating away and he's like, 'Oh, I know you!'"
Underwood said that Isaiah "has fun" at his dad's games and that the tot has already taken his first spin around the rink!
"He's had [Isaiah] on skates," she said. "I mean, he had to hold onto him the whole time, but that's such an important part of his life and he just grew up on the ice! I think that he would definitely want to have that love of being physical with Isaiah because he is such an outdoors man and he loves sports and he loves hockey and all that stuff. I think they'll share that."
Today, more than a decade after getting her start on Idol, Underwood also weighed in on rumors that the singing competition series could be returning to the small screen -- and whether she'd want a role on the show!
"You never know! I mean, I'm all about things that give people opportunity, you know? I know that without that show and that experience, I wouldn't be here right now. I feel like it's made for people like me," she said, adding that she hasn't heard any official word about a reboot. "I don't know anything!" she said with a laugh.
"I've had my time on reality competition shows," she says, brushing off the possibility of serving as a judge or host. "I think it would be really hard to be in the judge's seat. I don't know, I've been on the other side of things and I feel like I'm just gonna do what I do and enjoy watching them."
Underwood returned to the Idol stage just last year for a jaw-dropping performance on the series finale. Re-live the moment, below.