They assume that children should not start gaming, reading comics or doing other non-productive things like
ゴロゴロする from the morning, noon or any time in the daytime.
After thinking for hours, I realized it's not right to translate
から into 'from' here. The feeling or sense of
から seems different than 'from'. It's interesting to know that "from the daytime" doesn't sound right in English.
から comes with anything like morning, noon, daytime, night, today, yesterday and so on. The thing is, you can say
Xから even if it is time of X. So something like "from the daytime = in the daytime" happens in Japanese.
In your sentence, the kid started
ゴロゴロする in the daytime AND the speaker is also saying that in the daytime. Also, yes,
から can make connotations like "from such a time".
- [said in the morning] Are you going to study (start studying) now?
- Do you study (start studying) in the morning?
- Will you study (start studying) in the morning?
- Do you study in the morning?
- Will you study in the morning?