[KiwiBird]

In the middle ages it was normal among the commons to immediately kill dwarves or other physically handicaped babies. This was less so the case among the higher born, that said Tywin could have easily killed Tyrion at birth, claiming he had died together with his wife because of problems during childbirth. He could have easily shut up everyone who knew differently. The fact that Tyrion as a dwarf is alive proves that tywin would only go that far in dealings with his son, regardless his reasons. Very much unlike sam's father. Personally i felt that when Tywin told Tyrion he was still planning on sending him to the wall alive and reasonable well, he was saying the truth.