Maybe they should've taken that baby to a doctor instead of blaming it on the ghosts..
Indeed, not to mention getting the blood tested to see if it is really blood. I believe blood can be tested for a lot of things, I mean the amount of things they can deduce from it on house is awesome. Like what part of the body the blood came from... pretty sure they would be able to tell if it was supernatural!
But no, it's ghost blood.
Also the eldest daughter watching TV, yeah because it's so hard to believe she was watching TV and heard her mum get up so quickly pretended to be asleep. I'm sure I'm not the only one who has done that before!
And a knocking sound when they first moved in could you know, be a neighbour welcoming them to the hood? With all the doors bolted up they most likely just went home...
Maybe I'm just overly cynical because I've yet to experience anything, or maybe I have and just dismissed them, I don't know. 90% of what I have seen/read about it could easily be people lying or someone tricking them into believing. It's in ghost busters best interest to keep people believe this type of thing, not to mention ghost walks (ie my sisters hen night!) and haunted hotels.
Just because I don't believe doesn't mean I haven't thought about what they are though! My personal idea is they are some form of EM radiation/interferes or something which can store a persons brainwaves (possibly with some side effects and only at certain states of emotion, ie death?) which would explain a lot of things I think, without them being just dead people
Meh, occams razor, people be crazy! If you believe enough the mind can warp reality to fit it. (and possibly warp REAL reality with it

)