It looks like your friend is talking about her cat, not babies. Here's what she said: "She's telling me that her cat, Tatze, has given birth to 3 kittens. The little ones are so adorable, and she's also wishing she had a cat too, sadly" So, to congratulate your friend, you could say something like: "Huge congrats to you on the new kittens! I'm sure they're just as adorable as you said"