Pls. help to find/i.d. a movie

[Agent Oda]

Hello, new here. I'm trying to identify a movie I saw as a child, thought maybe users of this forum could help...

The movie I am looking for is one from the late 60's or early to mid- 70's, it's either a possessed child or antichrist type movie. It may have been Italian and dubbed into English, but what I remember is that the dubbing seemed off-timing, like a Bruce Lee movie.

What I remember from the plot is either a boy (around 2-3 yrs. old maybe) was either possessed or the antichrist (but I *think* he was possessed). There were parents, and some guy who helped them cure the kid.  

The only scene I remember I think is the ending: the family is on a ferry or cruiseship maybe, they think the child is cured, but we find out they are wrong because the kid throws a car off the boat, causing the car of some other guy in the movie to drive off a cliff.  

Anyone who has a clue about this, much appreciated.

[Shadowphile]

The only  'Antichrist' movie I know of from that era was 'The Omen'.

[Agent Oda]

It definitely wasn't the Omen or Omen II - I own those :)

It was something a bit more obscure. Unfortunately, what I've described it really all I know about it.