when iris was growing up, tree hugger was in and out of fluttershy’s cottage a lot. it was reasons kinda beyond young iris’ understanding - tree hugger was an orphan, and struggled financially often, so had no family to go to- so more often than not, fluttershy let her stay in exchange for sanctuary work. discord sort of resents it, and thinks tree hugger is taking advantage of his wife, but iris doesnt understand or care this pony is SICC.
 
iris learns a lot of her chilled out vibes from tree hugger, who frequently entertained her with “healing auras” and “cleansing rituals.” - and the lil draconequus ate it all up.  
iris has no more magic in her than the average pegasus pony, and cant summon it like her father- but the fact that tree hugger, an earth pony, no magic herself, could perform this type of “aura magic” made her feel so much better, and it was something she could learn too! discord thinks its all rubbish (as does angel bunny, who unfortunately gets roped in a lot) - but tree hugger is adamant that its real, and so is iris.
 
its not the only thing she picked up from tree hugger, though… she adored her in every way, and wanted to be exactly like her, but well. she unfortunately picked up on a lot of tree huggers less positive traits: iris became a bit more lazy, and a lot more careless. instead of dealing with her issues or her insecurities, particularly around her lack of magic, she prefers to just completely ignore it all together. what you can’t see can’t hurt you.
 
i was also initially weirded out by the idea of like. weed 420 ponies but. i mean. if we goin there: tree hugger definitely does. That. and is potentially a harmful influence on iris in that regard. doesnt understand its kinda not appropriate to offer drugs to a 12 old.