Sorry, at work so need to be brief. Thanks for all your feedback.
Iona, we were planning to pronounce it Yo-na. Is this correct? I think this is how I've heard it pronounced before, similar to Iola and Ioan. We live in Wales, and are both half welsh. I should know this, but IawnCont mentioned that she pronounces it Yonna. She's probably correct. We don't live in a welsh speaking area of Wales.