Dear Jenny,
I grew up with divorced parents and I am thankful that none of them had full custody. My brother and I lived mostly with our mother. Even though she argued and disagreed with my father’s mother, she urged us to stay with our father from time to time. He was not the best father, but lets not dig any deeper into that. In a couple of years we had grown quite a bit. Spending time with our dad impacted every aspect of our lives, but it had a more profound effect on him. He is no longer the person he once was nor is our grandmother the same. Once they had started to focus their attention on us rather than our mother they became warm-hearted and caring, which they were not during the first few years. What I am trying to say is that the said person might not have the perfect attitude towards your children now, but that can change with time. You should not worry about that at the moment, for worry will do nothing but waste your time and leave you busy doing nothing. I am not saying you should not pursue full custody. By all means, you are free to do what you want. In my opinion both decisions would be equally right and wrong or in other words…just different.
Best regards
Momchil