My eldest is 7. Her behaviour over the last few months has significantly deteriorated - the only warning that seems to work is if I threaten to call her dad and tell him what's been going on. I hate it as the term co-parent barely applies to him - he has no overnights and sees our children for an hour or so per fortnight.
I don't know whether to just find a way of dealing with her behaviour myself or involve him. I highly doubt when I've told him in the past that he has actually spoke to her sternly/told her off as doubt he'd want to come across as the bad guy for the little time he sees her.
Also it sets my teeth on edge involving him in any parenting really as his reasons for leaving very specifically relate to parenting and the children so I think why should I ?!