Yeranen Yaakov linked to an excellent article by Rabbi Pinchos Lipschutz titled We Really Care.
The Lakewood Scoop writes about the petirah of a young child who was struck by a vehicle. Below is a comment posted under the article.
The girl is named after Rebbetzin Kanievsky… One of the most special women Klal Yisrael had. In her biography from artscroll page 335 there is a special letter that Rebbetzin Kanievsky wrote to parents who lost their young children. May she be meiltz yosher for Klal yisroel. http://www.thelakewoodscoop.com/news/2014/12/tragedy-toddler-niftar-after-being-struck-by-vehicle.html
I turned to page 335 and found a letter from Rebbetzin Kanievsky to Mrs. Kletzky, written after the murder of Leiby Kletzky.
Parshas VaYigash - It's Never Too Late