Me and my family are shifting to a new place in 2 weeks Inshallah. But unfortunately that apartment has only 2 bedrooms. I only have 1 sister and we have love for each other. I and 15 and she is 17. We used to sleep together in same bed till I was 12 but then our parents transferred me to the 3rd bedroom. We both have our own single bed but my question is that can we sleep in the same room?
Islam permits "khalwah" (seclusion of a man and woman without a third present) between mahrams. An adult male does not incur sin upon himself if he sleeps in the same room as his adult sister out of necessity, and shares closet, bathroom, dressing table and other items of the room with her.
It is permissible for a man to sleep with his sister on the same bed as long as the bed is big enough for two persons, their awrah (which are private parts in case of siblings) are covered, and have separate blankets.
The Prophet (pbuh) said: "Command your children to pray when they are seven years old, and beat them for (not offering) it when they are ten, and put separation between them in bed."
Putting separation between them means not letting them sleep naked in one bed (like they used to do in the childhood), sleeping in their clothes without touching one another, and having separate blankets for each.
Ibn Muflih said: A boy who reaches the age of ten should be prevented from sleeping naked with his sister or any other mahram. This was mentioned in al-Mustaw’ab and al-Ri’aayah.
https://www.islamweb.org/en/fatwa/422176/adult-brother-and-sister-sleeping-together https://www.islamweb.net/en/fatwa/249073/adult-brothers-and-sisters-sharing-the-same-room https://islamqa.info/en/answers/78833/can-a-man-sleep-in-the-same-room-as-his-sister