Go out of your way to make the point:
May God's blessing be on your family as we remember the miraculous birth of the Lord Jesus Christ.
And hubris filled atheists and snot nosed redditors alike will quickly point out with froth at their mouths that christ wasnt actually born on christmas and the holiday was "stolen" from the pagans, much in the same way we "stole" the land we live upon today. They fail to understand history and have arbitrary points of origin to which they base all their ("infallible" "scientific") claims.
Theyll find the light and the way eventually as I did. They can't be shown the truth, they have to meander their way through darkness until they find it. Telling someone they're wrong is a sure fire way to have them double down and slight you for believing in fairy tales.
Being atheist, I don't really care about when you celebrate a religious birthday. You didn't "steal" anything, lots of people have the same birthday.
Well the idea among many is that Christmas is a fake holiday. It was "originally" a pagan holiday that the Christians co-opted or "stole," so that invalidates it.
But never do they take into account that its always been special time of year throughout all cultures and civilizations. No, they draw a line in the sand, and that is imaginary line invalidates every cultural transformation afterward.