Displaying Data from Multiple Layers in One Map Tip

Is there a way within a Map Tip for one layer, to Display data for another data layer within that layer's map tip?

In other words, if I have two separate map layers (Current Flood Zone & Proposed Flood Zone) & I would like to display both 

flood zone designations on one map tip. Seems like it can be done but have not been able to display data within a map tip if it

is not within the layer the map tip is created off off... Any suggestions?