John Gill Commentary Genesis 30:21

"And afterwards she bare a daughter, and called her name Dinah." — Genesis 30:21 (ASV)

And afterwards she bore a daughter
Which some writers, as Aben Ezra observes, say, was at the same birth with Zebulun, a twin with him; but being said to be afterwards shows the contrary: and called her name Dinah ;
which signifies "judgment": perhaps she may have some reference to the first son of Bilhah, Rachel's handmaid, whom she called Dan, a name of the same signification; intimating as if it was a clear case that judgment went on her side; and that by the number of children she had, it was plain God had determined in her favour.