Hezron was the father of Ram. Ram was the father of Amminadab.
Aaron married Elisheba. She was the daughter of Amminadab and the sister of Nahshon. She had Nadab, Abihu, Eleazar and Ithamar by Aaron.
Ram was the father of Amminadab. Amminadab was the father of Nahshon. Nahshon was the father of Salmon.
Nahshon was the son of Amminadab. Amminadab was the son of Ram. Ram was the son of Hezron. Hezron was the son of Perez. Perez was the son of Judah.
Here is the family line of Perez. Perez was the father of Hezron.
Amminadab was the father of Nahshon. Nahshon was the father of Salmon.