Hi Bearchic,
I don't think anyone can fully understand how you feel, unless they have lost a child. It's so hard to wrap your brain around. I guess the only comfort is knowing that she's with God. I've learned through life experience, that we're all here to learn life lessons and teach others as well. Perhaps God felt her soul didnt need to learn any lessons and that her soul was pure/complete. I suspect this experience has made you a more compassionate person because I've read your numerous comforting posts to others here.
I think it's a good thing that your children are comfortable in a cemetary. I was never exposed to death until I was 24 and it was very upsetting. But death is part of life, but it's hard when it happens to young people or especially babies.
Last summer 2 days before school started, a boy in my daughters class, lost his 4 yr old brother to a drowning in their backyard pool. They had just installed the inground pool 2 days before. He and his siblings were all playing in the front yard, when he went into the backyard. Minutes later his siblings tried to find him and the older brother found him. He's the one who dove in and pulled him out. The whole school community were shocked, especially since the parents are wonderful parents and safe - but it only takes a second. It was extremely sad to see a 4 yr old lying in his coffin. The first thing we think is, WHY and unfortunately we as humans can't find a satisfying answer.
The only thing we can do is keep their memory alive and not become bitter ourselves. Since you visit her on special occasions, try not to let it make you sad. Instead look at it as you're including her in the happy occasion. My thoughts and prayers are with you and your family.