No, Kids, I'm Not Always Fair!
As my children enter that delightful stage where they fight over all sorts of random little things, the time also comes when I have to ponder issues of what’s fair. Kids are great at pointing out when things are unfair.

On the other hand, I don’t want to overdo it. I can still remember as a kid not liking my grandmother’s chocolate chip cookies because she counted out the number of chocolate chips for each one, and just poked them in on top. That was how she handled her kids arguing over who got the most chocolate chips in their cookies.
That’s just not me.
I go more for the philosophy of letting it all balance out over time. I won’t say my kids are always delighted with this idea, but since for every cry of “that’s not fair” I can point out another time when that child got the best of the deal, my kids have a bit of trouble arguing that one with me.
They do try sometimes, of course. My oldest is particularly good at trying to come up with more reasons why things should go her way. Honestly, that pleases me. I want my kids able to stand up for themselves. She may or may not sway me, but she’s trying (sometimes very).
Seriously, I don’t believe you need to treat your kids perfectly equally. They do need to be treated fairly, but from a grown up perspective more so than from their own. You don’t want to build resentment but you don’t want to let your kids determine what’s fair all of the time either.
Sometimes things seem unfair to kids because of age differences. This goes both ways. My son gets mad because his sister, being older, can do some things he can’t. My daughter gets mad when her brother has fewer responsibilities. It seems unfair to each of them, but as any parent knows, you can’t let kids do things inappropriate to their ages.
I also just encourage them to work problems out on their own. I’ll start them on the path to a fair solution, sure, and make sure my daughter doesn’t take excessive advantage of her greater years, but it’s not impossible to teach most kids to figure out fair solutions together.
I hope that this way my kids will grow up understanding that not everything in life will go their way, but they can keep trying. Children should steadily be encouraged to be more independent, so they aren’t expecting their parents to solve every problem that comes their way.

I 100% agree. It’s a huge mistake to try and always be “fair”. I love them both, I respect them both, I take care of their needs. I have no interest in playing their “fairness” games, especially since kids’ definition of fair seems to be very different, and a lot less flexible, than grownups’.