OP here.
Below is more detailed situation:
$19,000 is all direct subsidized loan, so there is no interest accumulating now.
We can do without borrowing but it will lower our savings to under the 6-month-worth of income emergency fund threshold.
After graduation, we can still save 6 additional months during the grace period and we can pay if all off without interest.
This will indeed lower our savings to under the threshold. However, since we don’t have to save for tuition anymore, we can build the emergency fund quite fast.
My husband is a bit worried to go down the threshold. (and he believes paying little by little will build her credit history)
I say pay it at once even though we will be under the threshold for a few months (maybe 4 to 5 months.)