thank you for the replies!
yes, my way of realising this colour of hair was still used with G3s also was via accidentally fading the hair of my Cherry Blossom (III - I think. I am really not a G3 expert
we call her Spider Pony, because she lives a somewhat upside-down life
). the difference is that while I like her with the faded stripes, I don't think I would like Secret Wish as much, so I'd rather prevent her hair from fading if that streak is prone to that.
thank you for the info on the very similar two pinks SunbeamV! I hope she really does have the less fading-prone hair, I'd love to keep her out with my transparent G1s (Sunspot's mane is already faded so she doesn't mind to be out). they are on top of a shelf next to the wall that is furthest from the window in the room, so they get no direct sunlight, but still, with time indirect sunlight also does its work.