I'd run a mile. This is only a 3mo+ that as far as I can tell you have very little dealings with... IMO it sounds to me like you are more attached to the idea of this filly than the filly itself. I agree with frank, this will not end when the filly is "yours", it will continue for as long as you own this horse. I'd leg it now before getting anymore attached to the horse.
On a side note... I don't know what type of progress you want her to give you on a youngster - there is little to nothing to be done with the horse at the moment and bar it getting bigger there is little to report progress wise.
Stop for a minute, open your mind, learn. You may not agree with what I say, I may not agree with what you say but we will both learn something new.