Since it is at Christmas when she tells you these things, I'd say she is missing them and thinking of what might have been had she carried them to term and had them. I had one myself before I had my daughter Rie and her brother and I don't know if I have ever told her about it. It is not a secrete by no means but just one of the many sad things that happened in my life.

Why should you be mad about it? Maybe she was just trying to save you the burden of missing them or wondering what might have been too....