Why not simply tell your DH that you do not want to go to public places with SS3, until DH teaches him appropriate behavior? Why is this so hard for him to recognize and do?

Put it on your DH. It's not normal for adults to chase toddler around public spaces. My parents didn't require harnesses or strollers (if we were capable of walking) when out in public. We were told how to behave and if we didn't, we went home. And god help the kid that ruined it for the others.

We also weren't allowed in restaurants until we understood the rules. Good table manners, please, thank you and no thank you and ordering off of the kids menu. No exceptions.

My parents raised us the same way you raise dogs (except for eating and drinking out of bowls on the floor and using the yard as our latrine), they were the alphas. They were in charge. We were not. When we were good, they brought us dead things to play with (kidding but I'm still using my dog analogy) and when we were bad, they nipped our butts.

I honestly don't get why this is so difficult for so many people to understand these days (hello DH??). I was raised with rules and boundaries and I didn't turn out to be a serial killer (that you know of). My parents were in charge, we didn't interrupt them without getting in trouble, if we broke the rules, we were punished. We helped clean, do laundry, cook and work in the yard. In return we received clothes, food, shelter and when there was extra money....fun things to do. My parents looked out for us. Despite the chores, I had a lot of free time. I was encouraged to do well in school and got my butt kicked when I tried to play sick and stay home.

And god help me if I ever caused a scene in public (such as ran around to the point where my parents had to chase me down). That was a beating offense.

This is gonna sound dumb but have you explicitly stated that this is a "Date Night" (or rather, "date weekend"). Because if you don't some of us guys just naturally assume that any and all outings are family outings by default.

I feel for you!! I dealt with similar issues before I disengaged. It just really blows. You have to stand up for yourself. I held it all in for WAY too long and it was one of the biggest mistakes I have ever made. My husband's brat was an absolute terror from 3 on, and I quietly allowed myself to be subjected to it for almost 2 years out of fear of upsetting my DH, causing a rift, etc., but after going thru more Hell than most can even fathom, I had to disengage. I had to speak up. I had to tell the truth and become assertive. These DH's are just blind, denying, delusional, guilt ridden, idiots. All the wah,wah,wah, boo hoo bullshit over skid ALL. THE. DAMN. TIME. GRRRRRRRRRRRRR!!!!! Nothing makes me madder or more disgusted. DH used to try and force skid on me all the time and I allowed it. Not anymore. I go nowhere with him, I do nothing for him, I do not interact with him or his bitch mother, I do not pick him up, I do not do ANYTHING. I want nothing to do with him. I do not want him around. I do not like him. I do not miss him. I do not want him anywhere near me. Once I finally started asserting myself and taking my life back, I felt so free. DH is still an idiot, but I at least am out of the loop for the most part with his mistakes.

I so feel your frustration. My husband was the same way (though not anymore, the blinders have been blasted away). He never wanted to vacation anywhere unless SS was with us, otherwise he felt guilty and SS would cry and whine about not coming along when DH would tell him about our trip. My SS was mannerless when he was 4 and remains so at 15. I was fortunate--he lived with his mom several states away from us until just this year, so I only had to deal with him in the summer (which was pure hell every year). My DH was Disney Dad personified, and SS was an ingrate shit starter from the beginning. I made a genuine final effort with him when he moved in with us, but after he started all his bullshit again, I quit. Like Fedup, I do nothing at all for him or with him if I can manage it and I completely disregard his useless BM. Since life here is soooooo difficult that he has tried to run away three times (trust me--even his therapists agree that we expect the bare minimum from him),it is my sincere hope he will not return here after his summer visit with her; I would not miss him in the slightest. He's a cancer in our house. Of course, she's so useless she doesn't even have a room for him, so he'll be staying at his Grandma's...and that probably kills my pipe dream. But for now, I can dream a little.

SS was in the habit of leaving his shit all over the house too, until some amazingly insightful poster here suggested to pick up the stuff he leaves out and hold it for house duty ransom (or donate it, throw it away, or whatever works for you). If he wants it back, he has to earn it. Not sure if you could do that in your house considering the age of SS and the DH factor, but it has worked wonders for the common areas of the house. Now if we could just figure out a way to reboot his "manners" and hygeine settings completely...ah, but it will never happen. He still takes 30 minute + showers and doesn't use soap or shampoo, and slurps even the most solid of foods.

Also, I'll bet your 3 month old will be easy and well mannered at 3 years--SS at 6 will be even more obnoxious and rude. I know my 3 year old is. Maybe you'll get lucky and the SS's halo will break on your husband's watch and he'll finally appreciate you for being such an amazing tolerant woman