If your friend told you that her cat just gave birth to five kittens, then there are 5 babies. The sentences says, "Ang pusa ko ay kakapanganak lang nang limang kuting." "Ang pusa ko" means "my cat," "kakapanganak lang" means "just gave birth," and "limang kuting" means "five kittens." So the full sentence translates to: "My cat just gave birth to five kittens." Therefore, your friend has 5 new kittens to congratulate her on.