Kareem is Laila's son, and Laila is Amir's sister. Tariq is the son of another one of Amir's sisters, Sara. Since Sara and Laila are siblings, their children, Tariq and Kareem, are first cousins. Therefore, Kareem is correct in calling Tariq his cousin.

Maya is Tariq's sister, and she is also the child of Sara, who is Amir's sister. This makes Maya Amir's niece, as nieces and nephews are the children of one's siblings.
Amir has a brother named Omar and two sisters named Sara and Laila. Sara is married to Faisal, and they have two children, Tariq and Maya. Laila is single and has a son named Kareem. During a family dinner, Kareem keeps calling Tariq his cousin. Is Kareem correct in doing so? Additionally, how is Maya related to Amir?

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