A recent article in the New York Times "Why Sisterly Chats Make People Happier" states:
"...it’s true that talk is the reason having a sister makes you happier, but it needn’t be talk about emotions. When women told me they talk to their sisters more often, at greater length and about more personal topics, I suspect it’s that first element — more often — that is crucial rather than the last."
So here is proof, you both really do make me happier. Even if our communication forms are dependent upon 21st Century technologies, you can't stop science.