You could try wetting her hair and giving her a good conditioner treatment. If that doesn't work you could boil some water and dip her hair in it. After combing it out it should be silky and soft.
A big thing you can do to protect pink hair is to keep it out of the sun. Sun makes pink hair white as snow.
You can fix frizzy hair by dunking the hair in boiling water and combing out the tangles while it's still hot.
Dunno about keeping pink hair from fading though, I think it's just an age thing.
Whippetluv wrote a great tutorial for the MLPTP FAQ Also which is this one :
Whippets Wonderful frizzy hair tutorial ( includes curling)
@@whippetluv writes~ This idea really works.
Step 1... Frizzy haired pony
Step 2... Boil water
Step 3... Dip hair in boiling water
Step 4...Lay pony on a flat surface and comb out straight. I usually try to put a towel underneath of it to absorb the water. Do step 3 and 4 several times *if you want truly straight hair you are now done. Just stand pony up and comb hair how you want it to stay forever.
Step 5... Separate a small section of hair and curl around a cut off straw. Use a bobbypin to keep in place(hint..put the crinkled side of the bobbypin inside the straw to avoid a crimped look)
Step 6...Put curlers in all the hair. Go ahead and dip in boiling water every now and again. You want hair to remain hot and steaming while doing this.
Step 7...Leave to dry overnight. Then carefully remove bobbypins and slide out straw from the top.
Step 8...Enjoy your curly haired pony! The heat of the water changes the plastic and the hair will remain curly! No products needed!
Curls I have made in ponies has lasted for years! Frizz be gone!