Your friend seems to have said that her cat has given birth to 3 kittens. These baby cats are apparently quite adorable. You can congratulate her on her new additions to her little feline family, expressing your affection for the cute kittens too. Something along the lines of: "WOW Lisa, congrats on your kitty having 3 precious babies! How exciting and adorable. Cats are such precious companions. Enjoy this special new chapter with your little purr babies. I'm sure they are absolutely melting your heart right now!"