It seems your friend shared wonderful news on Instagram, and you want to congratulate her on the arrival of her new babies! From the message, it appears that her cat, named Tatze, has given birth to 3 little kittens. They must be absolutely adorable! You can congratulate your friend by saying something like, "Congratulations on the new additions to your family! I'm so happy for you and Tatze that everything went well and the kittens are doing well. They look so cute!" I hope this helps!