The Second Trap

I was playing a game with my youngest last weekend. The church nursery has an old Blue's Clues book that has different coloured shapes in it. I started to ask him which colour each colour was and what shape each shape was. He got some of the colours, but not all (he always got yellow, he loves yellow). He didn't know his shapes either. That got me thinking. Did his brother know his shapes and colours at the same age? (2 1/2). I think he did. I started to feel terrible. Have I fallen into the second trap?
You have heard and seen the second trap right? It's the trap of everything gets done with and for the first child. You have more time alone with them simply because there isn't another child taking up your time and attention. The second still gets time with you, but it is often shared time. I know I don't read as many pre-school basics books with my second as I did my first because I read to the both of them at the same time. (He may not know his shapes, but he sure does know the differences in construction vehicles).
Is the second trap inevitable? Sometimes I think it is. I also wonder if being aware of it helps decrease it. I know I've started to spend a little more one on one time with my second since I started to clue into this. I've also started to realize a benefit that my first child never had, an older sibling to teach him things too.