Gwen Stefani is having a hard time with the fact that her boys are growing up, just like so many other parents out there. As a matter of fact, the former chart-topper recently went on the record to admit that she's feeling “devastated” that her youngest son, Apollo, has just started kindergarten.

According to Entertainment Tonight, the 49-year-old Grammy winner says that she was hit hard when she realized that she doesn’t have any more children that are either in the baby or toddler stage. Instead, all three of her boys– Kingston, 13; Zuma, 11; and five-year-old Apollo– are all in school full time now. Stefani shares her sons with her ex-husband, Gavin Rossdale.

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Stefany recently admitted that she’s so surprised that parenthood truly makes time fly. She said that while she was very happy to see her kids start the next chapter– and school year– of their lives, she was personally devastated by it, too. Apollo is in Kindergarten, while his two older brothers, Kingston and Zuma, are in junior high.

Even though all the boys have a very close relationship with their father, they're also equally close to Stefani’s longtime partner, Blake Shelton. As a matter of fact, the singer says that they have a very close bond with the country singer and veteran The Voice coach. The couple began dating back in 2015 after they met on the set of the aforementioned reality singing competition show.

Stefani explained how close Shelton is with her three boys by saying, “Blake loves getting dirty with the boys. They’re always playing basketball or running around. They love it [at Shelton’s Oklahoma ranch] because it’s just the five of them out on the land, hunting or hiking.”

Shelton also said that he enjoys nothing more these days than to sit at home with Stefani and her three sons during the weekends. Instead of hitting the Hollywood party scene like other celebrity couples, they prefer to be "homebodies," so to speak. One insider also says that one of the reasons Gwen Stefani and Blake Shelton get along so well is because they share the same traditional Midwestern values.

Now as far as if the couple plan on getting married anytime soon, neither Stefani nor Shelton has made any comments about such a thing happening anytime in the future.