She may have just had a tummy bug that has upset her system a bit. Often they get temporary lactose intolerance from gastro or tummy bugs. I wouldn't be removing dairy from her diet permanently, but trialling her without it in her diet for a couple of weeks is a good start. Or you can try lactose free products first or go straight to no dairy. Often TLI will pass within a few weeks and they can happily go back to having dairy. If in a few you weeks you try dairy again and the same problem occurs, then its time to visit a gp for some testing. You don't really want to make it a permanent diet change without any confirmation that's its the cause of them problem. Also if you find dairy doesn't solve it at all, then you can try other common sources like fruit.
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