If you don't want to do any hard math now, a rough estimate is that you owe 15% of his wages Plus Housing, plus 25% of his wages only, in federal payments, and 4% of his wages only, in LA payments.
The tax payment for the first quarter (January-March wages) was due April 15 so it's late. The second payment (on April-May wages, due June 15) is also late. The third payment (June-Aug wages) is due Sept 15 and the 4th payment for Sept-Dec wages is due January 15, 2018. (The dates are correct, it's not 4 equal quarters.)
If this is the first year of owing estimated payments, you should be able to avoid penalties for late payment if the amount you pay in (from your withholding and his estimated payments) is at least equal to your overall tax liability from last year.
