How often does a parents of a child gave birth the same day as their birthday?

Well! congratulation to my cousin, her birthday was yesterday and she gave birth to her son on the same day as her birthday. So now her birthday is the same as her son, isn’t that something? That would be awesome, mom and son birthday is on the same day, would be a big party every year, it seems to bring the child closer to the mother in this case. Once a gain congratulation! 🙂