Taking to Reddit, the son who only goes by the name Beersie_McSlurrp, explained how his dead father had used the website FutureMe to send the emotional letter.
FutureMe allows messages to be scheduled ahead of time using 'some time travel magic' so that they are delivered to the recipient's mailbox unexpectedly.
Knowing that he was terminally ill, the man's dad decided to leave a poignant email for his son, reminding him 'how proud' he is of his child despite no longer being around.
Sharing the first paragraphs of the email on the forum, but no more as it 'got too personal', it was clear his father had a sense of humour.
The email began; 'Hello Son, I am talking to you from the grave, wooooooooo. I always said I will come back and haunt you.
'Seriously, by the time you read this, I will have passed on. Hopefully by now you have adjusted well enough to life without the old man and you have managed to help your mother adjust. I have complete confidence you will be taking just as good care of her as I did.'
The son explains that; 'He told me how proud he was of me for becoming the rank of chief (border security) and that he loved me.'
While many people might not enjoy receiving a message from beyond the grave, the original poster told the Mail Online; 'It was really nice to receive so long after he passed.'
His father also discussed his treatment and final days; 'I have a few thoughts to share with you and a few insights which we never got around to discussing in the last few months where I was still coherent (I'm imagining the morphine will have turned me into a bit of a vegetable. Hopefully I entertained you with some decent hallucinations or jibber jabber).'
FutureMe describes itself as a website that sends messages containing 'words of inspiration' or a 'swift kick in the pants' for either your future self or friends and family.