Chloe is, at her 2 years and 5 months, almost perfectly bilingual – there are some words that she mixes up but mostly out of laziness (and some that mpampá makes up too!).
I would say her first language is English, since that’s the one she uses when talking to herself, or babies and pets! But probably her Spanish is more advanced – definitely her grammar is.
The latest thing I’ve noticed though, is a context switch between the languages!!
She will be playing with her babies, speaking English, and talking in the first/second person: “Come here baby, I’m making some food you don’t cry”, and suddenly she’ll switch to Spanish because I’m around, but uses the third person! “The mami is going to Tesco’s and the baby is sleeping”
So I’ve decided to call them the pretend language and the narrating language 😁