いくつになったら in this sentence


いくつになったら買ってくれるの？

I'm not sure of the grammar used in this sentence.

いくつ-> Does this still refer to how many?

になった->Is the なった here a conjugation of なる (To become)?

Also is the の at the end of the sentence the contraction of an explanatory の
(e.g. the written form of んです)

Thank you!




I assumed that this sentence is used in a context where a child asks his
mother/father to buy him something, yet the parent said no, due to the child
being too young.

If translated directly, it would be something like "If I become how old, will
you buy it for me?"

いくつ can be translated as "how many" or "how old", and in this case, I used
"how old".

Omitting the details, なったら is a form of なった, which can be thought as a past-
tense of なる。

About the terminal の, I don't know the correct grammatical explanation, but it
adds the sense of questioning.

