John Gill Commentary Nehemiah 1:2

"that Hanani, one of my brethren, came, he and certain men out of Judah; and I asked them concerning the Jews that had escaped, that were left of the captivity, and concerning Jerusalem." — Nehemiah 1:2 (ASV)

That Hanani, one of my brethren
Either in natural relation, (Nehemiah 7:2) , or being a Jew of the same nation and religion; so Jarchi interprets it, one of my companions or acquaintance:

he and certain men of Judah ;
who came from thence to Shushan on some account or another:

and I asked them concerning the Jews that had escaped, which were left
of the captivity ;
who were returned from it to their own land; he inquired of their health and prosperity, in what circumstances they were, whether prosperous or adverse, whether they flourished, or were in distress:

and concerning Jerusalem ;
whether it was rebuilt, the houses and walls of it, and in what condition it was.