What do the icons next to a soldier's rank icon mean?

In combat, your selected soldier's rank is displayed as an icon at the bottom left corner of the screen. Sometimes a yellow star or a white cross will appear on top of it. What do these icons signify? Are there any others?

Solution 1:

The yellow star indicates the squad leader, typically the highest ranking or most seasoned soldier in the squad. There's not a lot of in-game indications about what this means, but from experience I believe there's a higher chance of your squad members panicking if this person goes down.

The white cross/plus indicates that the squad member is up for promotion... assuming they survive the mission :)