Wife and daughter both lack filters

My wife has had problems with thinking before she says things.  Sometimes, it involves offering something before thinking of the consequences or of the need to ask me if she can make the offer--"Sure, we'll make a whole batch of homebrew for you" or "Why don't you stay in our hotel room with us during our family vacation?"  Or things that put us in difficult situations, like telling saying something about someone that I had told her in confidence right in front of them.  Or something embarrassing--such as sharing my medical information (which antidepressants I am taking!) without asking me ("Honey, is it okay for me to tell them that you are taking antidepressants?")  

There is also a pattern of saying mean and hurtful things, especially about me.  She used to use the excuse that I shouldn't be offended because I "know that she doesn't think about things before she says them" and I needed to accept "that is just the way she is."

Yesterday, I took the kids out for pizza.  Our daughter, almost 9, asked a woman"are you a boy or a girl?"  The woman stated that she was offended and told me that I needed to deal with it. 

I told my wife about this incident.  The first question she had was actually about WHAT THE WOMAN IN QUESTION LOOKED LIKE!  I took this as "well, maybe she was justified" or "maybe it was an honest mistake."  I explained to my wife that our daughter had previously done things like referring to African Americans as "dark people."  I asked if it would be OK for her to go up and ask someone "Are you black or white" even if she wasn't able to tell by their appearance.  The point we need to emphasize is it really doesn't matter--treat all people with respect, even if you aren't sure what race/gender/etc. they are.

Granted, my wife has sometimes pointed out to our kids that they said something inappropriate and should not do so again.  But it really bothers me that she asked me a question that rationalized our daughter's rude behavior.  It strikes me as trivializing the importance of having a filter to decide whether or not to blurt something out.  It also strikes me as justifying her own negative behavior of blurting things out.