book her ticket sfo-dca-iah.....she can then check bags, etc.....you didn't say where in tx she will be, but i assume closer to iah otherwise book to dfw,aus,sat.....i believe that awards aren't subject to the open jaw rules, so should be ok.....also, consider a 1 way award for back to sfo if you have another 12.5k mi....

edit to add....might be uam fees or other considerations w/ her having a separate tickee....good luck