It's a tradition that dates back to your parents and it's handed down from generation to generation and can change over time too but not everyone does the same thing when it comes to opening Christmas presents. The question came up at a party over the weekend and some people were quite rigid in their Christmas routine.

Some people have the tradition in which they open one gift on Christmas Eve and it would be their Christmas pajamas so when they wake on Christmas morning they'll be wearing their Christmas pajamas. Others opened gifts on Christmas Eve so that the tree would be pretty much empty underneath it so there would be plenty of room for Santa to leave a ton of presents. While others wait until Christmas morning to unwrap all the gifts, including what Santa Claus brought them.

I know that with many families are split these days it's hard to keep a tradition going and many try their best to stick to it for sentimental reasons which is great.