This description seems to most closely match Cheerilee, the school teacher.
The description is vague, but if we are talking about a white unicorn, her name is Rarity.
Her name is Tra La La.
Be power ranges light pink sissy Nash 💮
The orange pony with glittery pink hair and a fireworks cutie mark is called 'Sparkleworks' .
With a butterfly Cutie Mark? That would be Fluttershy. There is a pony from G1 thats light pink and spends time with butterflies, her name is Posey.
purple and pink
Her name is Tra La La.
Be power ranges light pink sissy Nash 💮
The orange pony with glittery pink hair and a fireworks cutie mark is called 'Sparkleworks' .
purple colured hair but a little dark pink
Gogo
purple pony's an pink pandas are awesome yeah
pink and purple pocodot pony princesses
Strawberry Blonde hair goes better with pink than purple, so i'd say pink.
orange pink and purple
there are rare people born with pink hair but they tend to be albino.
I think you're thinking of Princess Cadance. She is pink, and has the crystal hear on her cutie mark. Check this link out to see if this is the one you are thinking of:http://images5.fanpop.com/image/photos/31900000/Princess-Cadance-my-little-pony-friendship-is-magic-31955391-646-646.png
because its not pink