Your friend mentioned that her cat recently gave birth to five kittens. So, when you want to congratulate her, you can acknowledge the arrival of the five new kittens. Here's a way you could phrase your congratulations in English: "Congratulations on the birth of your five kittens! That's such wonderful news! I'm so happy for you and your growing feline family. I can't wait to see them and watch them grow." And if you want to incorporate the Tagalog phrase you provided, you could say: "Congratulations on your new babies! Ang pusa mo ay kakapanganak lang nang limang kuting, sana ay maging malusog at maligaya silang lahat." This translates to "Congratulations on your new babies! Your cat has just given birth to five kittens, I hope they all grow up healthy and happy."