sarasal, the odds are excellent -- you can count on getting a walk-in permit, especially for a Thursday. Check out last year's unused permits for similar mid-week numbers.

The tough part, though, is the parking situation. If you can get a reserved permit, they give you a parking pass to park at Whitney Portal. It's even good for the night before so you can camp in the walk-in sites near the trailhead. But without the reservation, no parking pass! So you need to watch the online system and reserve one. (Even one, since there will be plenty of no-shows so you can add the second.) Bookmark this link, and check it regularly (make it your browser's home page!) Permits show up on-line, especially in the week before you want to go.

Best wishes to you and your husband! My s.i.l. just returned from an 8-month deployment (he's in Lemoore.)