I know that this is not totally on topic, but my own mom did not. We have had our issues (due to her enabling my brother who is an addict-it has been horrible), but I give her credit. She never talked badly about my dad and always encouraged us to spend time with him. He never spoke a bad word about her, either. And their respective families never spoke unkind words in front of us. My parents were married for 15 years; I was 12 when they divorced. My mom cheated on my dad, so it was messy, but they made it work for the sake of me and my brother. Up until about 2 years ago, my parents and my stepmom got along well enough--they could be in the same room and even talk. But, now, they are not speaking because of my brother. But, at least I had all those years (I am 39) with peace between my parents and no PAS. So, it can be done-my dad is clear proof of that. He could have said a lot of nasty things, but he never did. And he was deeply hurt.

BM1 doesn't. She doesn't see SS14.

BM2 did when she had custody. Now she doesn't have custody and rarely has visitation, so she doesn't PAS that I know of.

BM3 does....she has 50/50 and feels the need to compete because of the situation. We have all my kids all the time, and DH's older 2 all the time. She lost custody of her son, and only has her daughter half the time. She's always afraid of losing that split custody. It's funny, because I'd really rather not have SD6 full time, but just wish BM would set more structure and be consistent. Oh well, whatever.

Me. I'm a BM too & I never PAS, my exH never PAS. We never talked badly about each other & we only had 1 fight ever in front of our then young daughter. Since then we've always made it cordial. His wife also never said a nasty thing about me either in from of my kid or their kids. It worked. They're stable & all the adults get along.

My current DH's BM is the PASer from hell.
Disgusting how she doesn't even care how this has affected those kids that are truly messed up. The skid that lives with us, is disrespectful to us both. I disengage & ignore the rude teen but when he disrespects DH, I have no problem jumping down his throat anymore. He can believe his mothers lies about DH but don't ever display that behavior in front of me again. Because I disengaged, this reprimand has started to work recently. Before DH would snap at me for doing this but now he sees I don't have to tolerate it in my home.

DH's ex didn't PAS.

what is PAS?

My SKid's BM does not. But she is my wife. We have made it a point not to badmouth the SpermIdiot or the SpermClan to my SS. It is difficult. They are toxic toothless dipshits. However, aside from very early in our blended family adventure when he was ~2yo SS has never heard his mom or I badmouth the SpermIdiot and SpermClan or otherwise perpetrate PAS. When he was 1yo-2yo we would refer to the SpermIdiot as DickHead which somewhat rhymes with his name. We thought that we were very careful about not badmothing the SpermClan within hearing distance of the kid. It turns out toddlers have very good hearing. On one of the very few occassions that DickHead called to talk to the kid over the 17+ year CO my wife handed the phone to SS (then 2yo) and said "It's your daddy". The kid took the phone and said "Hi Daddy DickHead". My wife and I nearly gagged with shock and laughter. Fortunately a 2yo can easily misspronounce words so we were able to mostly pawn it off as a 2yo not speaking clearly. After that we made sure to never speak of anyone in the SpermClan other than by their name or title.

We did share facts when the SpermClan would load SS up with their vitriolic crap during visitations. When SS would come home and share or spout whatever idiot drivel they would vomit on to him we would calmly and rationally review the facts with him in an age appropriate manner. IMHO this is not PAS. This is arming the Skid with facts and is protecting them from the toxic half of their lended family. As he got older SS would ask us questions about topics that could have only come from the SPermClan that he was obviously fishing for information on. We would answer the questions factually and often would show him a CO, arrest record, etc, etc, etc...... out of our Custody/Visitation/Support files in our home office file cabinets. When he was in his teens SS would do the research himself.

Interestingly now that he is 20, working on his BSCS and serving in the USAF SS has little to do with the SpermClan. They rarely contact him. SS spends most of his leave time and weekend visits with my parents and my brother and his family. His mom and I are Expats so we do not see him often but when we are on vacation he aligns his leave so we can spend time together.

I'm a birthmom and I don't. I actually go the other route and talk kindly of the ex and SM when given the opportunity. I do this for my daughter. They, on the other hand, have been caught several times talking badly about me in the car, thinking DD was asleep in the back. I had a discussion with exH about it and, to my knowledge, they have not done it in front of her since.

As far as I'm aware BM doesn't PAS, and neither does my SO. They went through a period recently of not being able to even be in the same room together and didn't speak for months, but SO has always been very cautious about involving the kids in his relationship with BM. SD13 once asked him why he wasn't coming in to BM's house anymore when dropping her and SS off, and he just said that he didn't want to talk to BM because he didn't have any nice words to say to her at the moment, so he'd rather not say anything to her at all.

SO and BM are now best buddies again, "for the sake of the kids", and I kinda wish they weren't! But I applaud them both for never taking their anger with the other out on the skids.