I've been watching it on Iplayer. I accidently clicked on a later episode and saw that they'd had a baby, the baby was in the cot, all the ghosts were gathered around, Mike falls out of bed, bumps his head and says he can see them.
I quickly turned the episode off and found the one I was actually on.
I've now completely all the series and I didn't cone across this episode again. It ended with the house being turned into a hotel and Alison visiting for Christmas.
What on earth did I catch a snippet of? Does Mike ever see them? I'm so confused!