還有一個 id後面不止一人的。

I had that funny experience before in some Chinese forum. I supported some ID since I thought an  innocent individual was under assault. It turned out that there was another person using the same ID who was an older member from the same family. That changed the nature of the entire event. It was more like that ID manipulating the forum. I wasn't happy about it. But I never figured out why she revealed that truth to me. She was supposed to keep it secret from the rest of the forum. 

I was irritated and felt embarrassed by my own foolishness but had definitely learnt to withdraw a little before I trust my simple judgement from then on.