Hi Cindy..the citrus are in shock. First the long ride, then heat, cold. If windows were opened, wind, and if ac or heat was on, dry, stale air.
As long as the stems are green, citrus are alive. Remove yellow/brown leaves. Any leaves that fall on soil should be lifted and discarded. Dead leaves atop soil can cause problems like insects, rot, and even mold.
Place trees in the sunniest windows. South or west preferred. Citrus need humidity, so if the house is dry, turn on a humidifer. I mist leaves religiously, though some ppl think it's a waste of time. Still, I recommend it. If possible, shower/hose entire plant/s.
I don't know what outside temps are in Pa, but if it drops under 50-55 keep indoors. Normally citrus can stay out when temps are as low as 40F, but since they're in shock, I wouldn't mess around with fluctuating temps.
Water well, but allow soil to dry before adding more water. Did your friend repot? I'd leave citrus in their original growing pots for now. When they're in better health, out of danger, new foliage sprouts, then if needed, can be repotted to larger containers.

I'd be hesitant adding fertilizer, (especially chemical)unless your friend has a slow-/time-release Citrus Fertilizer. If so, follow container dossage and times.

If you or your friend uses Superthrive Hormon & Vitamins, add 10 drops per gallon of tepid water. Add to soil. ST works especially well on stressed plants.

That's all I can think of. For the record, he/she is living in dangerous territory hauling citrus out of Fl. (S) Toni