Handmade play changing

What's the best way to acknowledge the birth of a new baby who may not survive? - how to congratulate new baby

I have a friend whose wife just delivered a baby girl yesterday. She was born with only half a heart, and it is open heart surgery next week (one of many operations to come, if he survives). I congratulate you that you have a baby, but "Congratulations" does not seem fair. I would send at least one card, but I'm at a loss how I should handle it. Suggestions?