The desire to try and lighten his mood. To distract him from his concerns. To bring a bit of levity into his reflections.
The desire to offer a few words of comfort to him. To touch his elbow. To offer him a boiled sweet to take his mind off things.
The desire to smile and say, Never mind. Things will turn out alright.
The desire to be a solice to him. The desire to be a kind of good luck charm...