Whilst the question remains as to why Derek, like Suzy before him, has suddenly appeared from thin air without so much as a passing reference by his wider family (or from Pat, it seems!), this new brother looks likely to give the Mitchells yet another run for their money!
©BBC (2011)
Cast your minds far enough back, even Jack was an unreferenced addition before entering stage left to soak his future wife at his nephew's wedding ...
