Just to add another point of view, I’m not big on anyone saying things like they are good at math or not good at math…I think both statements can end up being counterproductive because they enforce the idea that someone is either good at it or they aren’t, when in reality no matter where you are right now, you could be better with more effort, if you choose…i think it’s better to have more of a growth mindset.

YES.

He doesn't always listen to what our DC is actually saying and often speaks out of his own issues or frustrations. I don't think he understands that DC takes in what DH said not merely as the opinion of another person but as an evaluation of their personhood by one of two people on the planet whose opinion they value most. Like I think he just doesn't get the gravity of that and therefore doesn't think that hard about it. So if he's annoyed with DC he'll say stuff like "You're so annoying" or "You ALWAYS [bad behavior DC only engages in sometimes but is really frustrating DH at the moment." I've talked to him about how DC is still forming their sense of self and if you constantly say "you are annoying, you are frustrating, you always escalate things, etc." then DC will internalize that and instead of doing it less, will come to believe that's just how they are and nothing they can do will help it. But it doesn't seem to sink in.

It's not all the time, just when DH gets particularly overwhelmed, but often enough that I worry about it.

Anyone else’s spouse do more harm than good sometimes when trying to “parent”? Where they just end up making unhelpful, or worse, harmful statements to their kids? Example, as spouse is explaining the importance of consistent, hard work, DD responds, “I know, I’m good at math but I could do better if I practiced more.” And spouse says, “No, you’re not good at math. And you know why? Because you don’t put forth the effort.”

Now, mind you, DD is getting A’s and some B’s in math. She is ‘good’ at math, but she could do better. I think my spouse in speaking this way to DD is chipping away (or worse, wholesale undermining) her confidence. How do I approach spouse without making them defensive? I don’t want to attack, but just point out alternative ways to approach DD. Not interested in starting a fight or coming off as ‘I know more than you’. I just happened to observe an interaction and I have an opinion about THAT specific interaction and not spouse’s overall parenting.