I had my daughter and two granddchildren staying with me - they went home last week - and they do seem to spend a lot of time with a tiny chrome camera and a mobile 'phone.
The thing is, they seem to giggle for a few moments and that's it: end of life of exposure other than to stick it on my machine too.
As a record of current life, for the edification of future civilizations or, less excitingly, just near-future generations, I don't think it will be much use at all. Unlike the large formats used by our ancestors, the tiny images are, basically, jpeg crap that isn't going to grace any wall in any museum.
If you take the Sally Mann ethic, then I do think it is a great project for a family, but only if the skills are there and the mind. I have no interest, personally, in shooting such pics, and I wonder what they really imply. There are very few family snaps of my doing - I found it practically impossible just to do it lightly, and of all those years, I have one shot of the granddaughters that's a double portrait in the drizzle (which doesn't show) and the other is a double of my son and daughter near a window at home in Scotland, which I shot just to use up the end of a roll on the 'blad, with a 150 stuck on it, that I'd been using for a job. And that's enough. The relative innocence is there - they were good kids.
However, I wish I had been able to do many more of my wife. I only have a print torn from her International Driving Licence from the 80s, which I kept, and a friend shot a jpeg of the two of us on the terrace one day. There are no negs, other than some colour 35mm ones that I know exist that we used as location illustrations for a recce we did in France. She hated cameras and being in front of them, despite (or because of) working beside me on the jobs we used to do. There are some files from the D200 that I did of her sitting at a café table after one of the chemo courses, but it doesn't even look like her. My memory gives superior results.
Bitter sweet is perhaps what it all ends up being.