My kiddos LOVE the white chocolate bears from Vitamin World they run $9.99 for 40 and if your daughter is so sick, she should have 2 a day, but then after she gets better it would be 1 a day. I recommend these because you don't have to fight them to get it in. And, you don't have to hide it either.
Rainbow Light also makes a gummy one, I think they are around $18 a bottle, I saw them at Target, but have gotten them yet. They look really good though. Rainbow Light makes everything from Food and so there is nothing artificial in it, so I always like this brand, but sometimes they are just not yummy enough. So these would be good if she likes them.
I hope she gets back on track and feels better soon!
Oh, if she starts getting really really stinky gas or poops, it just means it is working, but if she says it is uncomfy the she might need to start slower and give her a chance to work up to the 2 a day dose. Yogurt is ok, but it just doesn't have the same effects as the actual probiotics themselves. Also you can get Belly Juice which is in the refrigerated juice section and is about $5 a quart, but it also works really really well and my kids love it. I buy it when its on sale or I have a coupon because of the cost.