The pic of Bam's little girl on the bike brings back a memory. When our son was about that age, we took him and our daughter bike riding on a similar trail. Our son was in front of me just like in that picture, and the girls were behind me. Out of nowhere, a training wheel feel of the son's bike without his knowledge, but he just kept riding along as if nothing happened.
Until my wife announced that he was doing so well without his training wheel, at which time he realized what happened, veered left into the grass, and then crashed.