Parenting decisions are made by the parent a not you. Any fallout from these decisions is also the parents problem.
In theory I absolutely agree. The problem comes when there are implications and consequences from those decisions for the rest of the household (or even just you).
For example, if my husband chooses to let his daughter give me dirty looks throughout dinner, it does affect me. Directly. I don’t get to enjoy my meal because he’s too scared to tell a 7 year old off.
Even worse when I have my own children to consider. His decisions about feeding his children have an impact on how and when I can feed my children. And their behaviour is likely to influence the baby. If he lets them run around and scream in the house it wakes him from desperately needed naps. And so on.
The issue is getting HIM to understand that he doesn’t get to just go whatever he likes. He needs to think about the effects on everyone else in the household. He isn’t parenting (if you can call it that) in a vacuum; the other people in the house matter too.
I have to consider everyone in making my parenting decisions. I don’t let my son sit in his room blathering away to his friends as they play videogames online while my husband is trying to work in the next room. Or after my stepson has gone to bed. He has to go downstairs and be quiet and considerate of others.
Sadly the consideration (like too much in this marriage) seems to go mostly one way. And doubly so if it’s about the VIP members of the household. For example, I had a big fight with my husband because he’d (without asking) decided to take a day off work and have his children for an additional day. It would have been fair enough, except that my son was doing online school (live lessons) all day, sitting in the kitchen. All I said was that my husband would need to take his children out somewhere and he was such a dick about it. He genuinely thought that I was unreasonable for just telling my son to sit in his room (and sit on his bed to work) so that his children could watch tv/run around/play videogames in the open plan living room attached to the kitchen. And he should just put up with all the noise upstairs if they wanted to play in their rooms. Because he didn’t want to just take them out somewhere. Nor did he ask me about any of it.
Apparently my son’s school work was just not worthy of consideration at all, because my husband fancied pretending he was having more time with his kids, but was actually going to ignore them while they were here. Sure, it’s ‘just one day’ but it isn’t fair, and it’s representative of the broader pattern of not considering anyone else’s needs, just his own wants. And seeing any compromise on his part as ridiculous.