שלא שינו שמם

What was the most popular Jewish name at the time they went down to Mitzrayim?

answer:

 חצרון 

Each one of 70 Yordei Mitzrayim  had a different

name, except for the two Chetzrons.

One Chetzron was the son of Reuvain and

the other was the son of Peretz (Yehudah).

*Chetzron (son of Peretz) was married, when he was two years old.

His brother Chomul  was one year old when he got married.

(probably the youngest person in Tanach to get married)

*Midrash Tanchuma Shemos