Mates of State, one of our favorite married-musician duos (and that genre’s numbers are growing), showed up the other day at NPR to perform a Tiny Desk Concert.   And they brought along two additional Mates.  Check the assembled Mates ensemble perform two songs (Sway and Desire) off their  recent pop-trove, Mountaintops, and one of our all-time favorite compositions of theirs (My Only Offer) off of 2008’s masterful “Re-Arrange Us” album. Check ’em out below.