Hello KJ,
The answer to your question Karim, is yes, it is possible. Distance healing with Reiki, can provide comfort if his higher self is willing to accept such comfort.
Anyone attuned to Reiki level II or higher can assist you in your wish to send your relative healing energy.
Please let us know your relative's name and location, so that we who can send, may send our healing intentions to him.
Om Shanti,
Maria