1) The moment her adrenaline kicks in either the entire response gets shut OFF -she couldn't poo if her life depended on it-, or it will come raging on and she'll wet her pants and poo her pants. ((Depends on how much fear/stress/fear/anger gets turned on.))
If it turns into a battle... you're wasting your time. Plain and simple. The moment she gets upset, you'd have to beat her (literally) to make her be able to go.
2) In the vein of keeping things "fun"... Explain about "sneaky pee" & "sneaky poo". When you don't have to go, but you can still go!
3) Some kids and adults are once a weeker's. If you're a once a day person it probably seems insane... but I DARE you to poo every hour. Go sit down and push something out. If you do, you get an adult sticker (martini, $50, whatever). You will be INCAPABLE of pooing every hour, no matter how cool the prize, because your body just doesn't make poo fast enough. It's a sign of an efficient digestive tract (that it's using every last bit of what goes into it) and is completely normal and natural.
Adding all 3 of these things together:
- The on the toilet after meals is a GREAT idea, as long as it's NOT a battle. It works for a lot of kids IF AND ONLY IF they're not freaking out over it. So have this as a goal... and not a starting off place. Give her a book to read, tell her she DOESN'T HAVE TO poo... this is just to get her body used to sitting for when she needs to later on, and let her sit and read/color/whatever for 5-15 minutes. (don't worry about hemorrhoids yet, when they're intentionally trying not to poo they're keeping their bums tight... and are less likely to get hemmorrhoids than someone sitting in a chair. Worry about long sitters with relaxed bums in a year or two and you're shoeing her out of the bathroom)
Relax a bit yourself. Your daughter probably isn't a once a week'er, but she's also probably not a once a day'er, either. Try every OTHER day at most. Especially right now when she's freaked over it.
HINT: A little vaseline on the *outside* of her rectum will smooth things along / make things hurt less. And it feels kinda icky, so the natural response of people is to kinda wiggle and relax. Which also helps with the actual pooping. But it REALLY helps with the "It makes it not hurt" lessening the fear.