My only points here are
1. ASK ABOUT OUR BABIES! Yep, we might cry (probably will), but we cry all the time anyways. If you don't ask about them, it's like you don't care about them. It might be uncomfortable for you, but we live this every. single. day. Deal with your discomfort for 5 seconds.
2. There is nothing you can say to fix it. Nothing. It's okay that you don't know what to say. Actions speak louder than words. Send a card on anniversary dates, participate in memorial events, leave a snack on our porch, leave an angel in our tree, help us make a graceful exit when we are losing our shit, do 1 thing in memory of our baby. Not just the month after our baby dies, but 6 months, a year, 5 years later. It takes 5 minutes to send an email that says "I'm thinking about you."