Dragging and dropping multiple items,Dragging and dropping multiple objects

I am making a simple puzzle game with unity's UI elements. The user has to click and drag elements on a horizontal layout group to arrange them in a certain order to win. I want to make it such that dragging an element carries its right adjacent neighbour with it. Basically the user cant drag one element at a time. He has to drag two; the element he clicked on and its adjacent right. How can I add that feature. Am basically stuck at making the engine select two items in the horizontal layout at once. Any tips? ,I have a puzzle project in unity using the UI elements. its simple clicking and dragging of elements to arrange them in a certain order to win. Its on a horizontal layout with 5 elements. I want to make it such that when a user selects a element to drag, it drags its right adjacent neighbour along with it. Basically the user cant drag a single element at a time. My only issue is making it drag 2 elements at once. Any tips?