[ainiriand]

Not a good translation, it is the kid (a female kid). Problem is that we (spanish speakers) have letters to define the gender of the noun. The girl would be 'la chica'.

[dmurray]

”Kid" vs "boy"/"girl" isn't well defined in English: I would say they both refer to people of the same ages. If what you mean by kid is a very young child, prefer "baby" or "infant".

[guhidalg]

Some countries would use “la niña” instead of “la chica”. It depends on where you’re from. (Source: native Spanish speaker)