It's a fairly interesting read for dog-loving children. The plot is simple enough that it can keep the attention of the pre-school set (i.e., 4.5 year olds). I don't' recall any mentions of guns and certainly no graphic violence or anything of that sort. Do be prepared for some sad times. It is a little behind the times, as more and more people realize dogs needs to be inside with their families. Thus, you might expect some discussion about why the dog was kept inside an empty barn. Other conversations that might pop up include spaying and neutering and heartworm medication.
I thought the ending was on the abrupt side and sort of unclear. Is there really another stray dog that Frankie finds? I guess.