DD1 has not been told she's infertile. She has recently had an investigation for a gynae problem which could make things difficult (but hopefully not)
Oh good. Hopefully not indeed. I agree acknowledging her pain may not be enough, because while you want to give her hope that it will work out well, at the same time you need to help her to feel that even if the outcome of the referral isn't great that it's not the end of the world, and there are still many options, and even the childless option doesn't mean a life not worth living. What a fantastic role model we see now in Theresa May!
Unfortunately, until DD1 is pregnant herself, which could take some time, then I don't think its going to be an easy time for her. It wouldn't be anyway, as her friends start families, but having a younger sister surge ahead must be a particularly unpleasant medicine to swallow.
You are right that you cannot put things right for her, but avoiding baby talk, and helping her to feel her life is interesting to you and worthwhile whether she is a mum or not, may help keep irritation at bay.
Is it me or am I getting mixed messages
How do you acknowledge Easter.