Preschooler Questions

I knew the day would come when I would be asked by my 3.5 year old more details about the loss of her baby brother. I just didn't expect it to be so soon. Today I was rearranging the mantel and she started asking about the urn and why was it so special. I pulled it down and told her that Mommy had a baby in her tummy who was too little and not strong enough and he died in my tummy. She asked to see the ashes. At first she was confused as she looked at her very alive baby brother in his swing and asked if it was him, then I told her there was another baby in my tummy after her and before him (I decided not to go into detail that there were actually 4 other babies in my tummy in between. I figured that would get too confusing). She asked why he died and where he was, all the while I'm choking back sobs. I wasn't sure where to take the conversation...not sure what she could handle, not sure what belief system to set in place. We haven't dealt with death with her yet. We don't have a specific religious denomination that says in black and white what happens when we die. I consider our family to be quite spiritual, loving, and accepting of many beliefs and I want my children to find their own spiritual path as opposed to telling them what they should believe. I know what I believe and it is an ever evolving spiritual path. I'm not sure how to go about teaching spirituality in an open minded form and have struggled with it, and now I'm faced with it head on. I told her what my heart was feeling and in words I thought she could comprehend. I told her he's an angel and flew up to heaven, which is so high in the sky we can't even see it and beautiful like a park. I told her that every time I see a butterfly I think of him and I think it's his way of checking up on us to see if we are okay. She liked all of those things and was smiling as I told her about it. Bittersweet...