Good girls and bad boys (10)Logic Level 2
On an island, there is this strange pattern - boys always lie while girls always tell the truth. Once again, you encounter four children.
The oldest one says, "I have at most one younger sister."
The second one says, "I have exactly two brothers."
The third one says, "Half of us are girls."
The youngest one says, "I have three elder sisters."
How many girls are there?