Telling my 6 year old

Alyssa
So we are coming to the point where our daughter (6 yrs old) is starting to pick up on things and I am having to make up excuses to cover it up. I will be 10 weeks tomorrow, with a miscarriage previously in April. Any suggestions on when to tell her? I know by telling her, it opens a can of worms because she will be so excited to share it, but I also don't feel it's fair to keep it from her....