Priya is the daughter of Devika, who is Sanjay's sister. Since Sanjay is Rohan's father, Devika would be Rohan's paternal aunt. This makes Priya Rohan's first cousin on his father's side.

Arjun is Jaya's son, and Jaya is Meena's sister. Since Meena is Rohan's mother, Jaya is his maternal aunt, which makes Arjun another one of Rohan's first cousins, but on his mother's side.

Vivek is not Jaya's son because Vivek is the sibling of Priya, and their mother is Devika. Jaya is Meena's sister and has only one child mentioned, Arjun. So, Vivek cannot be Jaya's son but is instead her nephew through marriage since Jaya's sister-in-law, Devika, is Vivek's mother.
Devika is Rohan's paternal aunt, meaning she is the sister of Rohan's father, Sanjay. Devika is married to Anil and they have two children, Priya and Vivek. Jaya is Rohan's maternal aunt, being the sister of his mother, Meena. Jaya has a son named Arjun. Describe how Priya and Arjun might be related to Rohan, respectively, and explain why Vivek is not Jaya's son. Respond very briefly.