I'm kinda surprised they haven't already! They've already done a comic of it, and the story itself is already family friendly enough for Disney so they could probably do it while staying true to the original book. I'd love to see them tackle this one, especially if they do it in 2D and try to animate as closely as possible to the style of the first Bambi movie.

Like what glelsey said, they have already made a comic adaptation of Bambi's Children novel but it would be great if they made an animated adaptation (I prefer it in 2D animation) of it. I know that Wikipedia isn't the best source but it said on the "List of unproduced Disney animated shorts and feature films" article that an animated adaptation was originally planned to be made as a sequel to the first Bambi movie but it was scrapped. I'm not sure it was true but maybe that source came from the comic adaptation.