I am Brazilian, my husband is American and we live in France with our 4 months old daughter. My husband and I are both fluent in French and English, and he understands Portuguese pretty well and is working on speaking it.
I mostly speak Portuguese to our daughter, and he mostly speaks English. Our family language is English but with a lot of French words and expressions, and occasionally some Portuguese. And when French friends are over, we speak French, when Brazilians are over we speak Portuguese, when Americans are over we speak English. Basically, it’s a big mess and our daughter will inevitably hear both of us speaking these three languages, often all at once.
Should my husband and I make the effort of speaking “pure” languages at home when it is just “family time”, or can we keep using our mixture? Will that confuse our daughter? We are not worried about her French since she will be schooled here in France, but for the other languages that she’ll mostly hear at home and during vacation time with families, should we try to keep them pure?
Using several languages is not a mess, it is what multilingualism is all about precisely for the reasons you describe in your question: multilinguals need to be able to function normally among relatives, friends and workmates who happen to use different languages. Multilingualism is natural in your environment, and so is the use of different languages by the same person. You and your husband know this, and your girl will learn it the same way that you did, through experiencing everyday, real-life multilingualism. After all, if you want your child to become multilingual, there is no reason to avoid exposing her to multilingual adults, yourselves included.
It is also fine for you and your husband to go on using mostly Portuguese and English with your daughter. This will show her that these two languages are important to you parents, and so important to her too. Switching languages or speaking several languages is not confusing to a child. This is what goes on in all multilingual communities around the world – it may reassure you to know that multilinguals outnumber monolinguals, worldwide.
Language mixes (French and Portuguese into English, or vice versa) are not confusing either, so you don’t need to worry about keeping your languages “pure”, as you say. World languages like the ones in your environment are in fact typically mixed, because the people who use them have moved around and go on moving around for different reasons, like you and your husband, naturally borrowing and lending words and expressions in the process. If you feel that you need to “make the effort” to use your languages in special ways, don’t: language uses in a family should come naturally.
Here is a mix for you, just because I think it sounds better in Portuguese: um abraço para si.
Do feel free to contact me privately, if you wish to discuss these matters in greater detail.