According to multiple sources, the couple of eight months has every intention to wed, Us Weekly reported in its June 13 issue.
"Gwen and Blake talk openly about their future together," a Stefani family source told Us. "They say things like, 'When we get married...' all the time."
Stefani, 46, has three sons with ex Gavin Rossdale -- Kingston, 10, Zuma, 7, and Apollo, 2 -- but is still "totally smitten and wants to have a baby with Blake," added a Stefani friend. "Gwen is trying to get pregnant."
And Shelton, 39, reportedly can't wait to be a father, as he pushed for children with ex Miranda Lambert, who wouldn't budge due to her career.
"Blake was dying to have kids," a source said, "but Miranda kept putting it off."
While Stefani's three sons have become "closer and closer" to Shelton and "love" him, Stefani recognizes her boyfriend would be thrilled to have a biological child.
"Gwen says she wants to give Blake his own kid," said the Stefani friend, adding that the No Doubt songstress has her own motivation: "She wants a girl!"
Stefani also reportedly hashed things out with Rossdale already in that they've discussed how Shelton will play a role in their children's lives.
But before marriage and kids, there must be an engagement, and both Stefani and Shelton are busy touring for the next four months.
"Blake will ask Gwen's parents' permission before proposing," the Shelton source told Us, pointing out that Stefani's mom and dad "have been supportive of the relationship."
Once Shelton gets their permission, he'll allegedly figure out how to pop the question.
"He wants it to be special," continued the source close to the country star. "He'll do it when she least expects it."
As for their future wedding, few details have been discussed, but it will at least be a somewhat traditional Christian ceremony.
Shelton and Stefani met on The Voice set and began dating in October 2015. Both individuals divorced their former spouses around the same time, so they apparently bonded over the heartbreak and sought console in one another. Their friendship slowly sparked into a romance.