The third point of view:
One might ask, how had Pedro felt when his mother announced she was expecting a child? One word for that,
Awkward.
For christ's sake, he was eighteen years plus and would be taking his final exams soon, what doesn't seem awkward about it? He was eighteen years older than his soon would-be sibling - the age gap was simply absurd- nor did he ever picture himself changing a baby's diaper at age nineteen. Pedro had always imagined he would be the only child of the family.
However, he was excited as well. As a kid, he had always been lonely especially when his mom had to pull all-nighters. Being friends with Isabella and Anabelle then had been the best thing that happened to him. As the only sibling, he had always imagined what life would be like if he had a younger one to dot on, defend - and bully as well.