@Background Pony #445B
 
Well, I’ll tell you this: I didn’t start any of this.
 
(As for the names, it’s likely that Generations change over time, such like how G4 Rarity is white instead of pink like the G3 counterpart; besides, it’s supposed to mean something.)
 
Besides, even though it sounds like her name’s canon, we never heard it being said on the show, let alone the comic; in addition, she also goes by the name Snowheart thanks to the blind bag promotions, hence the questionable canonicity of nomenclature. Speaking of which, some prefer Snowheart rather than Coldheart due to the connotations thereof; then again, the personality you would have came up with maybe be your own headcanon, which I don’t mind. After all, making a full medical recovery from a serious and/or life-threatening injury does take a lot of work for the patient to do and not following procedure could undo all of the progress bit by bit.
 
After all, someone like her could have that disposition when dealing with such factors…

The names pretty much demand that these two be shipped.
 
(What I wonder is, why is the nurse pony who looks like G1 Sweetheart called Nurse Redheart, while the one who looks like Sparklebutt’s mom is called Nurse Sweetheart? Other than, I guess, the fact that FIM isn’t quite sugary enough for a character being named Nurse Sweetheart to not make a lot of eyes roll.)
 
I like to think that Nurse Coldheart isn’t bad like the name would have you think, but more tough-love. Getting better after a serious illness or injury is hard and painful work but you gotta do it. She pushes you to become stronger, but she knows what she’s doing. She’d be like a physical therapist or something; what she puts you through will make you cry like a little baby more than once, and if you’re not a child she won’t coddle you like one, but if you do what she says to the letter, you’ll be more than happy with the result. Ponies who have been told they’ll never walk again have gone to her, ended up saying more than once “If this is what it takes, maybe a cart thingy like that Discord lamp guy has isn’t so bad,” but in the end, were able to recover fully.
 
She’d also be the kind of doctor with little sympathy for those who don’t follow orders. If plan A doesn’t work, she’ll move onto plan B, but if you were told “take this medicine three times a day” and you took it now and again when you felt like it, and you didn’t get the result she said you would, that’s a whole ’nother story. Zero sympathy.