The 32-year-old model and "Lip Sync Battle" co-host gave her explanation after a fan criticized her for keeping her maiden name. The person said they will "never understand" why Teigen and other women wouldn't change their surname.
"You'll never understand the simple reason of 'because I don't want to'?" Teigen responded on Twitter.
Teigen had addressed the subject in an earlier tweet after a person asked "to hear the reasoning behind women who won't take their husband's last name."
"My husband didn't even take his last name?" the star answered, referencing how Legend's name is a stage name.
Legend's given name is John Roger Stephens.
He and Teigen share 23-month-old daughter Luna Simone, but have yet to think of a name for their unborn son.
"Boy names are really tough," Teigen said in an interview with "The Ellen DeGeneres Show" in February. "I don't even think he'll have a middle name because we can't even think of a first name."
"[With Luna], there was a blood moon happening," she shared.
"It was a very beautiful night. Really big, vivid, red moon, and just gorgeous. I have this love for space ... I just thought Luna was perfect."
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