Hello. I remember seeing a sims 2 machinima where a sim was crying and a ghost put his hands on her arms and looked at her sadly. It is the consolable crying interaction, but if I am not mistaken, ghosts cannot be made playable to interact with sims, because they always do the haunt interaction, and you cannot cancel that. So what happened? It would be nice to have ghosts interact with sims in sweet ways, but I assume you cannot.

I believe midgethetree has made a playable ghosts mod. I've not personally used it though so I couldn't tell you how it works, just that it exists.

I think there used to be some other ghost mods too, like skins and such, so it's probably a specially made playable ghost (or stand-in ghost) for the purpose of the film. Depends on how old the video is, i guess. I've seen at least one mod that enables the ghost locomotion "walk", too.

I think I saw it before 2014.

Smonaff's ghost hack has been around since 2006.
http://modthesims.info/d/202081/ghost-hack.html