I'm trying to understand the usage of 二つ下 in the following sentence.
When I read it without 下 it sounds like:
Shin-chan is my second cousin or something along those lines.
The issues is I don't understand the usage of 二つ let alone 二つ下 in this sentence.
Wouldn't it usually be written as シンちゃんの私のはとこです
I'm a bit confused here.