Please understand that it would be impossible for an attorney, any attorney, to tell you with certainty what will or will not cause you to lose custody, all we can do is provide some information and direction. To that end...
From what you've stated, I would suggest that there is not enough here to cause you to lose custody of your son. As I suspect you know, anything can be raised as an issue for custody. That could include the financial status of the parents, the mental and physical well-being of the parents and their ability to facilitate the relationship with the child and the other parent.
With this gentleman having just the one prior charge, and that one being rather weak, my thought is that it isn't enough, in and of itself, to change the custodial arrangement.
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