What is the most natural?
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Are you going to sleep because you didn't sleep last night?
If this situation is this morning and you stayed up from last night, 昨日起きていたから寝ますか？
Are you going to sleep tomorrow because you are going to stay up all night?
No I'm not going to sleep because I have to work
First sentence depends on the time last night or tonight. But Your question is のでorから.
In this case, both are correct. But usingので in polite Japanese is trend. Actuallyので means "cause of","due to".
からis "because" . But Japanese usage has changed to useので in every situation. So I assume other Japanese people would answer のでis natural.
If it's a little bit casual conversation, we tend to use 今日 or 今日の夜 instead of 今夜. 今夜sounds like formal.