Will it be a factor in a custody case if one of the parties involved got custody of a child through fraud and another party was never served. I know after a certain amount of time(in this case a year and a half) the best interest of the child is the litmus test. However, the person who got custody(in this case a grandmother) never told me she was filing, never served me, and filed the order under false information. Is credibility a factor? And also if in the original filing there was no allegation of a parent being unfit and the only reason for filing was the child was in the house would the argument of instability be a valid one at this point. Wouldn't the question be if the parent was unfit why was that never mentioned previously.