My Dad, passed away about 11 years ago.
Every year, on the day of his death... we go and have a nice family dinner, go to the cemetery to visit him, and make the day special.
And yes, it is 'celebrating' their memory.
My Dad, I imagine and knowing him, is also "there" celebrating with us. He would have WANTED us to, be all together as a family, in his memory. On that day.
We also do that on his Birthday, every year.
For Christmas, we also hang up a stocking for him, on our fireplace.
The kids, love that. And I also put things in it, for him.
Another cute thing to do is, and which we have done, is to get a helium balloon, attach a cute note message to it, and then let the balloon go up into the air... to the heavens. For that person.