I am the oldest of six children and as such started my mothering career with a "the youngest had it so easy" complex. So in my ultimate plan, which ultimately failed, I knew that I would be the queen of consistency. If I did it for one, I would do it for all. Completely fair (and completely stupid).
Fortunately it didn't take too long to realize my mistake. You could tell the kids were different when I was pregnant with my second. Turns out different personalities require different approaches. Who knew? Grounding one from TV is true torture while another HATES writing apology notes and the third breaks down in tears and corrects themselves at the suggestion that they've disappointed me.
Also, big surprise, kids were ready for different things at different times. My daughter was more than able to stay on her own for awhile at 8. My son...not so much. Some are natural cleaners, others need more, um, "encouragement." Some are dying for independence while their siblings need more help cutting those apron strings.
Some are physical, some throw fits, some talk back, and some are sneaky. One, who shall remain nameless, is a little bit of all four. Each one requires a unique approach. My plan of complete consistency was doomed to fail as soon as I relied on the randomness of genetics over exact cloning of myself.
And even if I had cloned me, things wouldn't be much better. Because circumstances change. With just two young preschoolers my schedule was pretty wide open, now with 4 in school and 2 preschoolers it is slightly insane. Plus, we make a little more than we did during undergrad and med school. Different size houses & yards, different friends & neighborhoods & school policies, different climates, all these affect parenting and make "complete consistency" not only unrealistic but also undesireable.
To top it all off, I've learned from my mistakes and tried to do better. I have accepted that the oldest is just made to be a guinea pig and no silly ideas of rigidity is going to fix that. I try to remember she had things that her younger siblings never had, too (like mom's undivided attention).
And so I find that my oldest waited for her bike till she was 6 while my 3rd had one at 4. Not a single kid went to preschool until #5. My oldest 3 didn't know Happy Meals existed until old enough to read, my youngest 3 think the world's ending if there is no toy in the bag. I volunteered weekly my first two children's first two years of school and I haven't been in yet this year. Things change. Kids are different. Mom is different. When it comes to parenting, one size just didn't fit all: one size didn't even fit one.