Finally, to is a mindset of self-efficacy. It is an assertion that you have control over your rest.
We are wishing them structure. We are wishing them a sanctuary that doesn't sag under the weight of the day. We are wishing them a suspension system that holds them up, rather than letting them fall. Sleep Tight
Linguists argue that "tight" in this context is an adverb meaning "soundly" or "firmly" (similar to "sit tight" or "hold tight"). Therefore, it simply means "sleep soundly." This theory posits that the rope-bed story is a retroactive invention to explain a simple idiomatic usage. Finally, to is a mindset of self-efficacy