Missing brick in internal wall, should we fill it? All manner of questions and solutions to problems and issues surrounding the subject of brickwork, blockwork and stonework

[Whichwayisup]

In the process of having my flat roof redone and insulation added to my ceiling the ceiling pb was taken down and there is what appears to be a missing brick/gap in the corner of my room just below the joists. Would anyone be able to advise me if there is a reason for this and whether I should fill it in or leave it alone.

Any advice much appreciated.
Thank you

[stoneyboy]

Hi whichwayisup,
Can see no reason for this unless there used to be a vent brick. If it does not go through the full wall width you may as well seal it up with another brick.
Regards S