A Five-Year Journal

I was talking with a group of younger friends last week, and one of them shared about a “Five Year Journal” she'd begun keeping lately.
It had been a gift she'd set aside and then found. Each date of the year had its own page, and each page had five sections, one for each of five years, each with only a few lines. The idea is that it's fairly easy to write a few sentences on those few lines each day, and so have a record of what's happening in your family.
So far, she's delighted with the results, remarking how even a few sentences can bring a whole event or day back into remembrance.
I've been keeping a similar journal the past few years, mostly with weather notes, but there are family notes sprinkled in. I've been keeping it long enough to know what my friend is talking about -- it's delightful to read back through this journal.
What if we kept a grandma's journal for our grandkids, each day recording some interaction with them, or some memory we'd like to share associated with the day? Even a few sentences each day would give them some kind of record of who we are and how we think about the world, what we've seen of the world.
You don't have to have a fancy book to do this; you could even do it online. The important thing is to begin!