Cooper will be the same age in this as he was in "One of Us is Lying", so he'll be a Senior in high school

Cooper Clay's mother had been pregnant for the last nine months and she finally gave birth a few minutes ago. She named the baby (Y/N). Her husband, who her other two children called Pop, had mixed feelings. He was a bit upset because he already had lawyer bills to pay due to Cooper getting accused of killing Simon, but he was also happy that he would have another son to teach baseball...or so he thought. Little did he know, his wife had given birth to a girl. He walked into the delivery room and saw his wife holding their newborn daughter. Their sons, Cooper and Lucas, walked in behind him with Cooper and Lucas's grandmother, Nonny, following right behind them. Pop's smile faded as he realized the baby his wife was holding was a girl