People consistently think that Blossom is the oldest sister now. She's more out-going socially and is more aware of what is going on around her.
Apple is often perceived as being younger than she is because she's still pretty short compared to her American peers and her expressive language still behind for her age, and she walks with a bit of waddle because of her feet and hips, but once people get to know her, they soon realize she's actually quite mature for her age, out-going and charming. She's very healthy socially and makes little friends easily. She can be a leader and a follower and tends to make appropriate decisions about which is appropriate for the situation.
Blossom and Apple do butt heads constantly now. Blossom pits herself against her little sister all the time. Apple usually comes out on top in verbal sparring. Blossom tries to treat Apple like I treat the three big girls and can't understand that I need to teach an intellectually healthy 4 yr. old in a different way than I teach three much, much older girls with I.D. All three older girls are often stunned when Apple can figure things out that they cannot. Our geneticist warned me about this and wished me luck. By the time she's 6, I'm sure Apple will be developmentally and intellectually ahead of her sisters.
Keeping the two little daycare kids that I still have has been good for Apple. Even though they are younger that she is, the little girl is very advanced verbally so they are on the same level in this area, though my daycare child will pass Apple up verbally in the next 3-6 months. Of course, Apple is much more mature over all.
Balancing everyone's strengths and weaknesses, abilities and disabilities, and allowing the younger ones to exceed the older ones requires very delicate parenting.