Looking for a part name/part number MPV 2004
 

One day this trim piece below the center of the front and back door was gone from my MPV, and I have no idea what happened to it. Any help identifying the part and where I might be able to get it (and put it back on myself, if possible) would be great.

The first picture is the missing piece. The second is where it's suppose to be (and is) on the other side of the van.

Thanks so much!

Forgot to mention - it's a 2004.

This area shows the rocker panel. Maybe it is called rocker panel insert or cover?