I have always found the recommendation not to skip a younger sibling based on the perceived effect on the older sibling to be baffling. If a child needs acceleration then why should they suffer the negative effects of not accelerating because it might impact the other child? Why is the older sibling more important Such that their needs can over ride the younger one's.
Surely the solution is to not ignore the potential impact of such a skip on the older child but to put support mechanisms in place for them as well.
Like others I have definitely seen the impact of one child being identified by other siblings as the smart one and so other roles being adopted. But it had nothing to do with grade skips and had a lot to do with individual personalities and a fear of being compared or not wanting to be challenged. It definitely should be addressed but not by discouraging the child who is doing well but supporting the one who is not reaching their potential.
Having said that all children have a right to be different as long as they choose their path for the right reasons not for perceived inadequacies and as parents we have an imperative to support each child individually and not deny needed opportunities.
