yes it can evolve
Shaymin does not evolve in Pokemon Diamond.
you need to battle with it alot to make it happyer then it will evolve
you don't it;s impossible.you can make swinub evolve but not piloswine.
Leave it with the nursery
you don't evolve it by a stone it will evolve by levels
lvl it until it evolves
the moon stone.
U Level it up of course
With an oval stone, you can evolve Happiny into Chanssey.But, you need to make Happiny hold that stone and then level it up in order to evolve.
make rhydon hold the protecter and trade it then it will evolve
Easy just use a leaf stone that's it.
you just trade it and it evolves during the trade. then ask your friend to trade it back