Diamonds are indeed a girl's best friend.
Carrie Underwood stunned on the GRAMMYs red carpet in a gorgeous black Nicolas Jebran gown that showed a whole lot of leg, but her sparkly diamond necklace also caught everyone's attention -- and it turns out it's a Valentine's Day gift from her husband, hockey pro Mike Fisher.
"It was a Valentine's present, that I don't deserve," the 32-year-old singer told ET on Monday. "It's mine to wear, so whenever I feel like it, I can be in my sweat pants, making dinner, wearing my necklace."
However, Carrie did reveal that she wasn't exactly surprised at the extravagant gift. "I kind of knew it was coming. We had been helping and working with designer Johnathon Arndt to make something special," Carrie shared. "We don't do a whole lot of gifts often, it was nice. This is many years' worth of gifts."
Obviously, the wait was totally worth it.
Carrie also dished about how her adorable son, Isaiah -- who turns one on Feb. 27 -- is currently enjoying tour life with her.
"He's doing really well. I mean, his world is kinda whatever we make it, right?" she noted. "So, we've always tried to keep everything loosey goosey, and he has a schedule, but it's not crazy 'cause we're in different time zones and we're in different hotel rooms and on the bus or back at home or whatever, so we kinda try to keep some consistency, but just trying to make him roll with it, and so far, so good."
The country superstar is keeping Isaiah's first birthday bash later this month pretty simple.
"A little party, just family and friends, people that are staples in his life -- it won't be anything fancy," Carrie said about the guest list. "I'm like, what do you get a 1-year old for a present? I have no idea so I've been on, like, Amazon trying to find presents for him."
"I'm gonna have to just go to the store and look," she added. "People are like, 'What is he into?' I'm like, I don't know, he's one!"
Carrie recently revealed Isaiah took his first steps just before she kicked off her Storyteller Tour. Watch her adorably gush about her son's latest milestone in the video below!