There is not a certain age for children to be separated from the parents’ room, but the Quran guides us on this matter as follows:
“Oh you who believe! Those who are in your guardianship, as well as those from among you who have not yet attained to puberty, should ask permission from you [before intruding upon your privacy] before the prayer of daybreak, and whenever you lay aside your garments in the middle of the day, and after the prayer of nightfall. These are the three occasions on which you may be naked. Beyond these [occasions], neither you nor they will incur any sin if they move [freely] about you, attending to one another. In this way God makes clear unto you His messages: for God is all-knowing, wise!
When the children among you reach puberty, they must ask permission, as those before them asked permission. God thus clarifies His revelations for you. God is all-knowing, wise.” (An-Noor 24:58-59)
The hadiths about separating children’s beds mention the age of seven or ten, but they must be about siblings sleeping in the same bed when we consider the verses above.
According to these verses, once children reach the age when they are able to ask permission for getting in, they must be spending the night out of the parents’ room already. The age of attaining to this ability is mostly much earlier than seven years, and it varies by the child. Note that, this is the maximum age until when the child can sleep in the parents’ room. There is not a minimum to it. That is why a certain age cannot be mentioned.