Christine Hartwell told Fox 25 she noticed her daughter Julia acting strange when she came home from her Pentucket Workshop Preschool one day. When she asked what was wrong, the 4-year-old told her "she was really sad about what her teacher did that day," Hartwell told the station.
Julia told her mom she had been reprimanded for calling someone her best friend and told not to use the term again.
"(Julia) said you know so-and-so, you're my best buddy," Hartwell, told WBZ-TV. "The teacher told her that she couldn't say that there in school."
The school did not comment to the Associated Press, Washington Post or other outlets about whether such a ban was official policy, but Hartwell told Fox 25 she received a letter from the school's director.
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"It has been our experience (which spans decades) that the use of the term 'best friend,' even when used in a loving way, can lead other children to feel excluded [...] which can ultimately lead to the formation of 'cliques' and 'outsiders,' " the letter said, according to the station.
Hartwell told the station her daughter now feels confused about whether it's okay to use the language.
"Even now she goes to say it in a loving way — 'I'm going to go see my best friend Charlie' or this one or that one — and she looks at me sideways as she's saying it and she's checking in with me to see if that language is okay," Hartwell told WBZ-TV.
The mom said the school's policy was "outrageous" and "silly," according to the Associated Press.
"I think it's ridiculous," Hartwell told WBZ-TV. "Children who are 4 years old speak from their heart, so they should be able to call kids anything loving - you're my best friend, you're my best pal."
The idea of discouraging the idea of "best" friends in schools is not new — though it does not appear to be prevalent.
A column in U.S. News & World Report in January titled "Should Schools Ban Kids From Having Best Friends?" said that there was an "emerging trend among European schools, and now some American schools as well" to ban the idea of best friends.
"My hope is that if we encourage our kids to broaden their social circles, they will be more inclusive and less judgmental. The word "best" encourages judgment and promotes exclusion," author Barbara Greenberg, a clinical psychologist, wrote.
Greenberg didn't point out any examples of schools that banned the phrase, but that didn't stop the column from sparking a fiery response from outlets like the New York Post,Chicago Tribune and others denouncing the idea.
Back in 2013, private school headmaster Ben Thomas in Britain told The Telegraph he supported the idea of discouraging best friends, but that it was not an official policy.
“There is sound judgment behind it. You can get very possessive friendships, and it is much easier if they share friendships and have a wide range of good friends rather than obsessing too much about who their best friend is," he told the paper at the time.