Became a father again

I became a Dad again yesterday with my wife giving birth to a baby girl. This is my second daughter. I feel fine but my parents are openly hostile. They are negative and truly wanted a son. They even gave my wife some medicine for having a son in her third month but my wife didn't take it. Right now, they are supporting it reluctantly but still bit angry with wife not taking the medicine, and bit disappointed about the baby not being a boy. Please get it that they are not making any scenes, but the disappointment can be felt. There will not be any celebrations or anything (which were there for my first daughter). It is disheartening. What should I do to convince them or motivate them?