Belief in the paranormal

Recently we moved in with my in laws and are currently looking for a home to buy. My in laws live in a home they bought in 1999 and it was brand new. They've never experienced any activity...until recently. We've all seen shadow people even during the broad daylight. My FIL even seen a toy car start up on its own. What's going on? Any ideas? I'm not sure why this is all just now happening.