Announcing to family after miscarriage

I had a MMC at 12 weeks last September and my sister in law just lost her first pregnancy after trying for almost 2 years. I got pregnant 2 weeks after she found out. My inlaws are devastated. They have already told us how sad they are about not getting to hold their 2 new grand babies before next Christmas. Now I am 8 weeks, my husband and I decided not to tell them, just in case anything were to happen to us again. I want our announcement to them to be just as special but I'm worried they will be too scared to be happy. Any tips from ladies who have expirenced a similar situation?