[Closed] We think we know people, but then they have secrets....

@ Philby & Mostly Balanced - thanks both of you for the advice, what you say makes a lot of sense. I'm hoping my attendance at my older daughter's graduation later this year will provide the impetus for her to 'accept' her half sister, and that in turn will pave the way for me discussing the subject with my younger one. I sense she's getting mature enough about relationships (at the tender age of 10!!) to make sense of it all, but like Mostly Balanced my biggest worry is that it'll make her feel insecure about our current family situation. Still, like Philby I'd rather she hear it from me and gets a chance to ask questions. Thanks.