The “one person, one language” approach is a popular method adopted by parents attempting to raise simultaneous bilingual children.
For instance, the child's mother might speak to him or her exclusively in French, while the father might use only English.
[1] The term “one person, one language” was first introduced by the French linguist Maurice Grammont in 1902.
He theorized that by separating the languages from the beginning, parents could prevent confusion and code-mixing in their bilingual children.
[4] In a 1989 study published in the Infant Mental Health Journal, Naomi Goodz found that fathers tend to adhere more strictly to the “one person, one language model" than mothers.