Reese Witherspoon says she doesn't quite know how her youngest son came up with his nickname for her.
In a social media post Wednesday, Witherspoon revealed her 12-year-old son Tennessee Toth calls her "Morty."
The actress shared the video as part of a social media trend revealing what the people in her life call her.
Among the list of names were "Laura Jeanne," her government name; "Reese," as her fans know her; "R Dubs," which she said her friends call her; and Tennessee's nickname for her, "Morty."
As for the "Morty" nickname, Witherspoon added a footnote, writing "*no clue why" next to the name.
Witherspoon shares Tennessee with ex-husband Jim Toth. Tennessee was born Sept. 27, 2012, in Los Angeles.
Witherspoon also shares a daughter, Ava Phillippe, and a son, Deacon Phillippe, with ex-husband Ryan Phillippe.
Witherspoon revealed Wednesday that her two older children stick to a more traditional nickname of "Mama."
In a Mother's Day post last year, Witherspoon shared a photo of all of her children smiling, along with a short caption showing love for her kids.
"The greatest gift of my life is being their mom 💝 Happy Mother's Day to all the moms out there!" she wrote at the time.
