I heard it from the oldsters when I was a kid. I don't recall hearing it since I grew up. I heard it once from an oldster in church, applied to a set of fraternal twin boys (five or six years old) – one of them was blue eyed with fair, straight blonde hair, and the other was brown eyed with dark curly hair. Their mom had arresting ice-blue eyes and curly dark hair, while their father was brown eyed with straight blondish hair. The thing that was so awful about that is the oldster had to have known that – the kids had grown up in the church.

I also recall the phrase in some books too – in Agatha Christie's And Then There Were None, for example.