Do second and third-born children really talk late?
"What the research says about birth order and early language development." Having observed my two youngest at an early age (they are 15 months apart) the oldest of the two was constantly speaking for the youngest one. I would ask for my oldest to let her sister talk but they had their own speech community. The younger one was always content to let the older one speak for her. It did not seem to me to hinder her language or speech readiness once she did start speaking for herself.