Carrie Underwood has learned that life doesn’t always go according to plan.
“We initially in our lives kind of wanted our kids a little closer in age,” the country singer and CALIA creator, 36, tells PEOPLE in this week’s issue, out Friday. “That didn’t happen, because God has a different plan sometimes.”
Underwood and Fisher, 39, conceived in early 2017, but she suffered a miscarriage. She then went on to have another loss in 2017 and a third in 2018, before their son Jacob Bryan finally joined the family this past January.
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There is a silver lining to the timing of the brothers’ births, though. Now that Isaiah is a little bit older, he’s willing to jump in and participate in tasks to assist his parents with caring for the family’s newest addition.
“Being almost 5 years old, he’s just so helpful, and he looks out for his little brother,” says Underwood. “And he’s good at [obliging] when you ask him to do something; he’s a very task-oriented child. So if you ask him to do something, he wants to feel helpful and he wants to do it and be a part of things.”
With Christmas coming, though, Isaiah is understandably a little distracted with getting his wish list ready for the man in red.
“I was telling him recently, ‘We need to sit down and write a letter to Santa,’ because then I feel like he needs to lock in what he wants Santa to bring him. So we’re going to have to do that,” Underwood tells PEOPLE.
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The American Idol season 4 winner had to remind herself of CALIA’s “stay the path” mantra after the birth of her second son, when she felt the societal pressure to have her body “bounce back” right away.
“After having my first kid, I felt like I bounced back fast. And then with Jake, it was like my body took a minute to get back to me. It was frustrating, because I’m like, ‘Why wasn’t it like the first time?’ ” Underwood shares with PEOPLE.
She adds, “But I’m four years older. That also helped me shift my mindset — I’m still working hard, wanting to be the best me possible, but cutting myself slack and just thinking, ‘Be kind to yourself.’ It’s amazing what we [women] do to ourselves. We’re probably all our toughest critics.”
For more from Carrie Underwood, pick up the latest issue of PEOPLE, on newsstands Friday.