The clue is in the shape of this patch on the kitchen ceiling.
Outside above the patch is a chimney. It looks like there used to be a fireplace or central heating boiler in the kitchen of this 1950s bungalow.
A look in the attic reveals that the chimney breast and chimney stack are almost entirely unsupported now the fireplace has gone.
There is considerable weight more or less supporting itself. The answer is for an RSJ or reinforced concrete lintel to be inserted below the unsupported structure.
Otherwise, someone could have a nasty suprise whilst eating their Frosties one morning! If the chimney is no longer in use you must never leave it unsupported when you decide to create more space by removing the fireplace from beneath it.