Efrat,
You've come to the right place!! And welcome to the USA!!
I moved from Connecticut to Michigan (663 miles) in September with my 6 cats. I was worried about how they'd take the ride. My fears were unwarranted. I put two girls in each carrier and the 2 boys separate. I didn't hear a peep out of any of them for the whole 12 hours.
If you're worried, you might want to talk to your vet. He may have some suggestions such as Feliway or Rescue Remedy (I bought some thinking I'd need it - NOT!)
Good luck with your move. Maybe we can set up a PT reunion!! Illinois isn't that far from Michigan (I don't think)
Since you have 4 cats, is there any way 2 can go in each carrier?? They'd keep each other company and would prevent you from having to put them in the cargo area (like putting your kids in there)
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