When to tell my kids

I am typically a firm believer about waiting until 12weeks to tell our children. We do have a history of having a miscarriage in the past at seven weeks.

But what is making the situation so different is that this Friday we are having our eight ultrasound. And then the day after that my parents, who live out of state, are coming into visit to celebrate my dads birthday. I really want to let them know if everything looks good on the ultrasound this Friday. But we want tell our children first.

Should we tell our children this weekend? Or at 12 weeks?

Our children are 13 year old and 4 year old