hi,my name is sandy, i have a six year old tortie,vu, every other month we have an episode where she can't go poop. she gets sick and makes very sad noises when in and out of the litter box. i've had her to the vet four times and each time they put her under and extract the poop. the dr. says that it turns side ways on it's way out. vu does not eat wet food, she drinks alot of water and she eats pro plan for digestive problems. i've tried pumpkin pie filling, cat lax, cat grass etc. what do i do? please help.