The childhood experiences with your sister have followed you into adulthood. That is reflected in my analysis.
--childhood best friend-reconnecting with undeveloped positive aspects
-I grew up with-following you into maturity/adulthood
But what other issues have followed you in adulthood? Are there any issues that you have kept private? The bedroom part may be speculating on the 'hidden' aspects related to sister or other issues not related to anything intimate. If there are issues of intimacy or sexual experiences then that needs to be looked at.
As for what someone says in a dream meaning it is what they think of you. It likely is saying something of what you think of yourself although it could be what they think. Your dreams are about you and depending on who says what and in what context what is said is something you saying to and about yourself. Or it could be what you perceive another person thinks about you.
Look at your early life and determine if there are other issues the dream could be addressing, other than the sister relationship.