Haider and Humeria are not at all related to each other. (Not by blood). Zoya is Gaffur's daughter and so is Humeria. But they have different mothers. Haider is related to Zoya's mum.
Zoya is Haider's cousin from her mother's side. So their mothers were sisters. That is how Haider and Zoya are related. That does NOT make him related to Humeira. Haider is not blood related to either Gaffur or to Razia. So how can he be Related to Humeria? Just coz Humeria is Zoya's sister doesn't mean she is Haider's sister too.
Biologically Haider nor Humeria are in any way connected.