My five year old plays in creative mode and is asking about how to get a wither skeleton to fight by his side (essentially taming it). Anyone know how to do this?
If a regular skeleton shoots at the player and it hits the wither skeleton, then the wither skeleton will attack the skeleton. Other than this occurrence, it is not possible.
As far as vanilla goes, it's not possible. There might be a mod to tame hostile creatures, I don't do a lot of modding though so I'm not sure. I'd recommend having a look on the modding forum and maybe on planet minecraft.