Sad news, six months late

Yesterday I was strolling the neighborhood and enjoying the weather. I noticed that our neighbors across the park has new stickers on their back windshields. Walking over, I read that they are memorial stickers for their young daughter who was undergoing chemo treatments. She passed six months ago :-(  

They are such a sweet family, and it breaks my heart even more to know that I didn't KNOW when it happened. Don't want to just knock on the door and start something, but wish I could let them know how sad I am for them...tell them my favorite memory was her zipping through wal-mart in the electric cart with her hannah montana wig and fancy hat on. 

She had the same subtype that my friends' son is in remission from, and I remember talking to them at the park at the last ice cream social and pointing him out, saying that he was in remission. I took it for granted that her treatments were going equally as well. My bad.