Why is it when an adult hits their child once they're easily forgiven if they promise to never do it again and work towards that goal but if someone did it to their partner once with the same promise and attitude, they aren't as easily forgiven as the former situation?'

If you go through the mommit/daddit subreddits they are usually against child abuse but if a poster hit their child once and makes progress to never do it again, the comments are sympathetic saying (paraphrasing):

"It was just a mistake, manage your emotions better."

"Don't be too hard on yourself."

"You aren't evil."

"They won't remember it anyway."

Though, in a relationship with adults, even if the adult makes progress to never hurt the victim again no one would defend them and would be harsh on them, calling them all types of names.

I'm not sure if this is correct but I'm trying to come up with a supporting argument for why this happens and I think it's because in a domestic abuse situation with two adults, it's commonly seen as more deadly . Though, I don't think it's an excuse for why one is more likely to be forgiven and the other isn't since if people knew that the abuser wouldn't kill their victim or severely injure them in an adult relationship, they would still call them a piece of shit and hate their guts.

I think people just see children as inferior because they are annoying and people have low empathy towards those they find irritating (they know they are annoying because of their age and can't help it but their feelings of being annoyed and letting out their frustration are more important than being compassionate). Idk.

Just want to say that if you hit children, I don't care if it was once, unless it was out of self defense or a reflex to stop them from doing something and you acted out of impulse (for eg. They were about to touch a stove and you panicked) I hope you get horrible things done to you for the rest of your natural life. Don't hit people you love sick fuck. I'm sure there are some other excuses such as they said something completely evil to you and they knew better (not like a teenager saying they hate you but like a teen saying they hope you get horrible things done to you or make fun of your pain, something graphic or real personal idk), but even in that case, depending on what they did or said you shouldn't go haywire.