Kalashtar sleep, but they don't connect to the plane of dreams as other creatures do. Instead, their minds draw from the memories of their otherworldly spirit while they sleep. As such, you are immune to spells and other magical effects that require you to dream, like dream, but not to spells and other magical effects that put you to sleep, like sleep.
Severed from Dreams
Raw data
{
"srd": false,
"name": "Severed from Dreams",
"page": 29,
"type": "entries",
"__prop": "raceFeature",
"source": "ERLW",
"entries": [
"Kalashtar sleep, but they don't connect to the plane of dreams as other creatures do. Instead, their minds draw from the memories of their otherworldly spirit while they sleep. As such, you are immune to spells and other magical effects that require you to dream, like {@spell dream}, but not to spells and other magical effects that put you to sleep, like {@spell sleep}."
],
"raceName": "Kalashtar",
"basicRules": false,
"raceSource": "ERLW"
}