If it's near her eyes and really bad, I'd call the doctor. I'm not sure if it's cortisone they use - there's also a medication they can take for anti-inflammation. Depends on the severity. You could try oral Benadryl to help the itch but it usually makes the kids drowsy. Maybe just try that at night?
For everywhere else, our pharmacist recommended Domeboro - it's an over the counter powder you dissolve in water, then soak washcloths or rags and just place them over the kids' legs, arms, whatever - it dries out the blisters and stops the itching. The calamine almost always itches as much as it helps because putting it on with cotton or gauze just aggravates the rash.
There's also something called Ivy Dry that helps dry up the blisters.
For the future, buy some Tecnu at the pharmacy - gardeners use it to get the oils off their hands and arms after they've found themselves in poison ivy. Rub it everywhere, then shower thoroughly. If you're careful, you can use it on the skin near the eyes as long as it doesn't go in. Some people also rinse off with dish detergent to get the oils off - stand the kids in the tub and scrub them down with undiluted dish soap, then rinse like crazy.
Tell your husband to wake up! LOL. But you can tell him where little boys can get poison ivy...like when they have to go pee, they touch things! My son had it really badly there!