Today the 7th is Three Kings Day, it is the night before the 3 Kings appeared according to what is written. The 6th that is important
Xmas eve is when he was Born 25th Dec but it took the kings that long to get there that the Presents were only given on the 7th Jan. Most Catholic countries observe this and so, Unlike the UK & US Xmas presents are exchanged on the night of the 3 kings Epiphany! which this year is the 6th of Jan
Hope this helps you understand The 6th is eve and the 7th is the day but anyway