How my dad became an atheist.

I used to debate religion and the existence of a god with my dad. He's not religious but believes in a creator, and he used to tell me that I would change my mind, like so many others, when my time would come up.

How ironical is it that he had to have a stroke three weeks ago that left him hemiplegic, and that the last time I saw him after that he told me that I was right, that there was no creator, no god?

It could just be the depression at being reminded of his mortality, I will see later, but does anyone here think that it is just a pseudo deathbed conversion that he will recant later? Anybody with a similar story? Should I try to find out his reasons?