John Legend Says Son Miles, 5, Had to 'Get Used to Not Being the Baby' After Siblings' Births (Exclusive)

John Legend's son Miles Theodore is adapting to life as a middle child.

While chatting exclusively with PEOPLE about his partnership with Pfizer and encouraging people to get this season’s latest COVID vaccine, the singer, 44, also opens up about how his 5-year-old son reacted when he became an older brother earlier this year after Legend and wife Chrissy Teigen welcomed daughter Esti Maxine, 10 months, and son Wren Alexander, 4 months.

Noting how it took his older two children — Miles and big sister Luna Simone, 7 — some time to adjust to the new additions in their family, Legend says, "Especially Miles. It took him a second to get used to not being the baby anymore."

"But he's really grown into being a really great older brother, and Luna's a wonderful older sister," the proud dad continues. "They love holding their little siblings, they love just playing with them, and they're embracing the big sister and big brother role very well."

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Legend and Teigen, 37, welcomed their oldest child in April 2016, before Miles joined as a new addition in May 2018. The couple later suffered a pregnancy loss with son Jack, their third child, in September 2020.

The family then welcomed daughter Esti earlier this year on Jan. 13. At the time, the EGOT winner first shared the news at a private concert. "What a blessed day," he told the crowd just hours after Teigen had given birth.

Legend and Teigen's family then expanded once more when they welcomed their baby boy Wren via surrogate on June 19, 2023.

Currently, Legend says that his oldest two kids are doing great, telling PEOPLE, "They're in school. Miles is in kindergarten and Luna's in second grade."

"Luna just started doing homework, which is fun for me because I like overseeing her homework, and I was always kind of a very precocious student," he continues. "So I get to relive that with my daughter and my son."

As for his younger two, the "All of Me" crooner adds that the infants are reaching some milestones of their own, and he and Teigen "love" being a family of six.

"Esti just started crawling a couple of weeks ago, and Wren is 4 months old now," he says. "They smile a lot."