What to do??

I have an issues, that I am not sure how to deal with. Right now it is okay but here in a few weeks we might be back to the same issues. Let me explain. Edward started going to Children's Church and Sunday School at mid-April. There are 2 teachers (they alternate weeks) for his class (4 and 5 yr olds), one of them seems to have issues either with Edward or what little kids say in general, I am not 100% sure which yet. She has been leave for 2 weeks but should be back in about 2 to 3 weeks. The first week she had Edward in her class, she came to the door as soon as she saw us. She quite huffily and rudely, announced to us that we need to "Talk to our son". We asked why, she said because Edward said that a Tuba sounded like a Fart. For crying out loud he is a little boy and pretty much all little boys would say something like that. 2 weeks after that, she meets us again at the door, and tells us that Edward said that He wanted a baby brother or sister, that mommy was trying to get one in her tummy. She acted like this was offensive. She acted like he was talking out right about sex, he is a little boy, he doesn't even know what sex is. I told her that he was a little boy and didn't know what that meant, all he wants is a sibling. I forgot at the time because I was so upset that I had told Edward (who has been bugging me endlessly lately) that he needed to ask God for a sibling if he wanted one, that he wanted to pray about it. So, I am thinking that this topic of discussion came up when prayer requests were asked for. I went to the other teacher, but I still dread when this teacher comes back. What would you do in this situation? I would love any suggestions.