Carrie Underwood is "excited" about her upcoming arrival

A source told People magazine: "She is as excited about the baby as [her new music]. The machine that is Carrie is fully on. She’s in full album mode."

Meanwhile, Carrie recently revealed she had endured three miscarriages in the last two years, and said she was left feeling “angry” by the ordeal.

She said: "I had always been afraid to be angry. Because we are so blessed. And my son, Isaiah, is the sweetest thing. And he's the best thing in the world. And I'm like, 'If we can never have any other kids, that's okay, because he's amazing.' And I have this amazing life. Like, really, what can I complain about? I can't. I have an incredible husband, incredible friends, an incredible job, an incredible kid. Can I be mad? No. [But after the miscarriages,] I got mad. [I thought], 'Why on Earth do I keep getting pregnant if I can't have a kid?' Like, what is this? Shut the door. Like, do something.

Either shut the door or let me have a kid."

Carrie's three-year-old son Isaiah is already bonding with his unborn sibling.

When asked if Isaiah is aware he's about to become a big brother, Carrie shared: "I don't think for real he does. He'll be really sweet and talk to my belly and kiss my belly. He's the sweetest little boy.

I mean, no kid can really know that their life is going to change.

He'll just have to share mommy."