@babiesX3 - I'm not an expert in human virology by any stretch of the imagination, but if I had to guess I wouldn't think it was all one virus. I mean, people can get multiple colds just weeks apart, and each one be from a different strain of a related virus.
At the same time, I don't suppose it is totally impossible. More likely, however, is that your daughter's lungs were not fully recovered from her first incident and that's what made the RSV harder on her when she got it.
In any event, it says above that the metapneumo virus belongs to the same family as RSV and pneumonia both, so the fact that those two would have such similar symptoms is not surprising.