Betty:
This is a tough situation. I definitely wouldn't burden my daughter with this unless I felt I had to especially considering she is already dealing with a difficult situation. The question for me is 'need' versus 'want' ... I would choose 'need'.
The 2nd of my two daughters moved out of the house in January before I came out to my wife. At that time the most I wore was some lingerie and felt there was a very low probability I would be discovered by my daughters (wife a different story). Now I dress fully en femme and if my daughters lived with us, I think there is a high probability of discovery. Even if I want to, I find it impossible to constantly suppress this urge to dress. I think it's worse to be discovered than to come clean. The 'coming clean' situation can be planned, managed and controlled whereas the chance discovery is much more volatile.
I may face the dilemma soon as there's a possibility the daughter that moved out in January will be back in May. They occassionally visit and my wife has already stated she does not want them to know - her feeling is that it would traumatise them. This too is an important consideration. For the record my daughters are 18 and 22 so I'm of the view they could handle it / my wife thinks otherwise.
In my situation, if I can avoid discovery by either suppression, very careful planning or whatever then I see no reason to tell them. However, if I feel I can't handle this, take risks when I can't resist the urge then I'd be leaning toward disclosure. I'd have to convince my wife to the same conclusion before doing so.
I agree with the point that as a parent, the children are the number 1 priority. However, in the case of coming out to my wife, our relationship was the number 1 priority. I eventually came to the conclusion that discovery (because I simply could not resist the urge) by my wife was a higher risk to the relationship than disclosing.
It's a difficult dilemma and I wish you and your daughter the best regardless of which option you choose.