My brother and I when I was in High School
From the perspective of the older child(ren), I believe giving them this younger sibling is going to be an amazing growth opportunity. No, I am not expecting my children to mature overnight. But, I do believe this will help along a very natural progression in their maturity and development. None of my children were old enough to appreciate the miracle of life or really helping in the house when any of my babies were born. That is all going to be very different this time. They have no idea how much change is coming, but I believe they are going to be over the moon for this little one and we are all going to love having a new baby El in the house!