A parenting expert says primary schools should discourage best friendships - because it's too "territorial".
Speaking on Good Morning Britain on Friday, Liz Fraser said she backed schools that teach pupils not to have a single "best friend" - which is the ethos at Prince George's school, Thomas's Battersea - because it makes children "possessive" of one another.
According to the Daily Mail, the mother-of-four, who said she didn't have a best friend herself while growing up, said she believes it's a good idea to have "broad" friendship groups.
But viewers branded the notion of preventing children from having one best friend "ridiculous".
Fraser said although she didn't think a best friend ban could be completely enforced in schools, she supported the idea because it "separates" children.
She explained: "It immediately [separates] this friend out as being different from all other friends, which immediately sets you into a mini group.
"Some children don't have a best friend, I didn't have a best friend, if I did have a best friend I think it's because no one wanted to be friends with us."
Fraser called on primary school teachers to encourage children to have a large group of friends, rather than one "best" one.
She said the concept of best friendships was more relevant to female pupils, and made little girls "possessive" of their best friends.
She continued: "Boys don't have best friends, they have mates whereas girls have a best friend. It's very territorial, it's quite possessive, and for me there's an element of it's actually not to do with this friendship, it's more about telling everybody else 'this is my best friend'.
"I think it's a good idea to try and keep things a bit more broad."
The debate arose because of recent news that some American schools have banned best friends because it can make children without one feel lonely.
Viewers were shocked by the argument. Many accused Fraser of not understanding why children need best friends as she didn't have one herself growing up.
One tweeted: "The only thing that got me out of bed & to school was to see my best friend! Let children be children."
"We've turned into a right nation of p******," another posted.
A third agreed: "They don't always have a concept of a 'best' friend at this age. Stupid discussion."
Psychologist Dr Mark Rackley said having a best friend was important because it taught children important life skills about forming relationships.
He also said having one particularly close friend was important to children who didn't have siblings.
Dr Rackley explained: "Where best friends really come into their own is with children who have no siblings so that best friend can be a substitute brother or sister.
"The best friend is the only supportive relationship that child might have so pulling that away might actually damage the child more than letting the child have a best friend."