No. A substantial change in circumstance is needed to change custody. What is that substantial change? And not to dad but to the children? That dad can prove? Slapping a child in the face matters not. How do you (dad) know that the child didn't smart off to mom and she cracked him/her across the mouth? Dad needs to have communication with mom and it is not apparent that he does. He also had something to do with the fact that the 7 year old was almost held back in kindergarten. What responsibility does he take for that? After all, HE CHOSE to move away from his children. Even though you state he had concerns about mom's ability to parent if she went off her meds.
One substantial change is that when they sought custody initially, Mom was taking her meds. Dad voiced concern over her instability, but he only won 50/50 physical custody. (he did have the kids more than that). At the time of the custody dispute, mom was not continuing to use drugs- she likely stopped due to the custody battle itself, or maybe she was feeling better and stopped on her own, I am not sure.
Another change is one that my husband just became aware of. Mom has been reported by the 10 year old to have been using a blue and black pipe in front of him. He described a plastic (he called it a sandwich bag) with green stuff that she was putting in the pipe. Although my husband cannot say for sure that marijuana was being used since he wasn't there, it does seem to indicate that given her history, there is a strong possibility there and maybe if the 10 year old is being exposed to drugs, it should be checked into.
The 7 year old was actually almost placed back in kindergarden instead of moving to 2nd grade. She has now been held back in 1st grade instead. Both my husband and I have spent a lot of time working with her- he hasn't just ignored the issue.
Yes, he CHOSE to move. Mom has moved away from the town they lived in also, and has changed towns approximately 6 times in the last four years. The other mom (of my husband's oldest 2 boys) also moved out of town. Both my husband and myself have kids from prior marriages, and we both moved to a town that was in between the distances from each of our kids. I happen to have custody of my son now, my older children are adults. We chose this area because not only was the economy better, but it put us at an almost equal distance from all of the kids. I know there are a lot of deadbeat dads out there, but my husband isn't one of them. He is completely devoted to giving his children the best life possible.
As for "slapping" the child in the face- you misunderstand. She repeatedly punched him with her fist along his face and his entire left side. Both the 7 year old and 10 year old reported that mom asked the 10 year old about if his dad had drank any beer while he was here. (dad has an occasional beer once in a while, usually after mowing the yard or something, and rarely in front of the kids, but mom has accused him of drinking heavily and this question has come up before.) The 10 year old responded that he didn't know. She screamed at him to tell her the truth and reached over the seat and began hitting him. While it is perfectly legal to use corporal punishment with kids in Kansas, hitting with a closed fist or in the head is not legal.