Explaining differences in language acquisition between siblings

[Ignasi Clemente]

Dear colleagues,

today I was lecturing on language acquisition, and a student asked me a question about her children. One of her children spent some time playing with sounds, and gradually, moved on through the different stages of language acquisition.  Her other child, repeatedly went from zero to one: he didn't play much with sounds, but then uttered one words without problems; he then played with one words, and suddenly, moved on to two words.  Other than general statement about cognitive maturation, and that children are different people with different personalities, I couldn't really answer her question about differences between her two children, who were acquiring the same language in a similar social context. Obviously, the second child had an older sibling than the first one did not.

This is what my student told me from her experience raising her children, and therefore there will be a bias of recollection. Also, I'm assuming that she is referring to differences at comparable biological age brackets.

Can I say more in terms of differences in production of language from a developmental perspective? I'm aware of the controversies around measuring acquisition in terms of biological age, but I would appreciate any comments or suggestions.

Ignasi