Well, sometimes you're closer to one than another and you'll want to continue with that one. I'm closer to my youngest grandsons rather than my older ones. My ex raised them and I raised the younger two. They're all with their mom now so I don't get any of them gifts anymore but when the younger ones are with me I often give them little things they want.
Like today, my two youngest were with me and I bought them both Fidget Spinners. One is ADHD and has SPD and the other one is on the spectrum somewhere but he hasn't been diagnosed yet.
It wasn't much of a gift but it was something they'd been wanting.
The older boy is moving out on his own and I'm sure there will be things he'll want. The next older boy is about to start driving and I imagine I can send him a gift card every now and then for a few dollars of gasoline.
SO I don't go out and spend a bunch of money on Christmas but I do little things for them when I have a chance to see them and do something special for them.