EDIT: I have a new question. What do you think about this idea?
The save the dates we are ordering are the typical DW boarding pass things. The guests who speak Spanish won't be traveling so a boarding pass seems silly. Maybe I'll just do some simple DIY save the date cards and print those in Spanish. That way we won't have to worry about ordering two different copies. I'm probably over-thinking this again...
I am going to order my save the date cards sometime this week. English is a second language for about 30-40% of our guests. All of those guests speak English very well and when FI and I are with them they only speak English, for me. I can only think of one person (FSIL) who doesn't really speak English.
So I was just wondering, since they are used to speaking English with us do you think it's okay to print everything in English? Or would it be more polite to print their STDs and invites in Spanish since that's their primary language?