Jamieson, Fausset and Brown on Matthew 1:11

11. And Josias begat Jechonias and his brethren--Jeconiah was Josiah's grandson, being the son of Jehoiakim, Josiah's second son (1Ch 3:15); but Jehoiakim might well be sunk in such a catalogue, being a mere puppet in the hands of the king of Egypt (2Ch 36:4). The "brethren" of Jechonias here evidently mean his uncles--the chief of whom, Mattaniah or Zedekiah, who came to the throne (2Ki 24:17), is, in 2Ch 36:10, as well as here, called "his brother."

about the time they were carried away to Babylon--literally, "of their migration," for the Jews avoided the word "captivity" as too bitter a recollection, and our Evangelist studiously respects the national feeling.