I'm not saying there is any excuse for kids (or people) to mistreat animals.

But, perhaps one of the reasons you see that in SKIDS is they often feel their lives are a bit more out of control.. having to live with dictated visitation.. rules of step parents... etc... and maybe it's kind of like the old trope of the guy having a bad day at the office so he comes home..kicks the dog.. because he can't kick his crappy boss.. not acceptable.. 

In your case.. you are also dealing with kids who have been taught pets are expendable.

I absolutely loathe any animal being mistreated, so I hear what you say. DH told me a shocking tale about how before he and BM got married, she allowed a couple of guinea pigs she owned, to die of neglect.  How come he still married her? I hear you ask.  SMDH.  Fortunately the SDs don't seem to be like their mother in this respect - SD29 has two cats and by all accounts treats them well.  But I agree, dysfunctional people often mistreat animals as well as other people.  

Nuts.  Mentally crazy. You can't change that 

Thankfully Little Idiot never mistreated the animals in our house. She's actually gentle with them. Having said that, when it comes to taking care of her own animals, she is lazy and neglects taking care of them (so in my mind, it counts as abuse).

Neither DH nor I would stand for someone hurting our animals. DH is as much on the same page as I am about this. (He actually once had a horrible nightmare a couple years ago about someone (random stranger) shooting our cats with a bow and arrow. It got him so upset he told me, that in his dream he got ahold of this psycho and gouged his eyes out! ... My husband is even tempered 99% percent of the time, he's not a violent man unless provoked then it's game on. We watch a lot of horror films so I'm thinking that's where he got the eye gouging idea from haha. I patted him on the back and told him he did good in his dream.)

Back in the Seventies, my mother ran an animal rescue out of our small ranch. I grew up surrounded by animals of all sorts, abused, neglected, dumped, or just lost. Those animals helped raise me - they taught me about pecking order, consequences for bad behavior, respect, empathy, patience, and the importance of consent. They were a lot of work but it was a wonderful way to grow up. 

OTOH, my DH's people are quite different. Druggie SIL and her two kids went through pets like crazy. I took in a few of theirs over the years, when they either had to move or got caught by a landlord for having unauthorized animals, and it always took a long time to make them feel safe. Another SIL doesn't like animals at all. As a young adult she acquired two cats, but they ran away. Hmm. Then there's OSD. In her first marriage, we babysat her young dog a few times, then it simply disappeared. Several years later, she asked us to pay so she could "adopt a dog for the gskids". I said sure, thinking it would cost a few hundred dollars to adopt a rescue from the local shelter. Imagine my surprise when she said she'd found the perfect purebred puppy in a state 2000 miles away - only $700 plus shipping and delivery! My offer of $200 was not accepted, lol. Some time after I dropped the rope I heard she'd managed to get the puppy of her dreams (a hound of notoriously fickle temperament), however at some point it bit her son in the face and was taken to the pound.

As an animal lover, I hate this too. I literally ran into traffic yesterday to save a baby crow in the road, yet I had to live with kids who don't understand how to treat animals for 10 years. It blows my mind how dense they are.

BM is like your BM. She gets an animal to appease the kids, then everyone stops playing with it or feeding it and then it gets given away or it just disappears. BM currently has a new fiance and they got a pit bull together. The poor animal gets left alone all the time and has separation anxiety from its previous owner. I wish the animal shelters kept records on these people who just throw away animals when they get tired of them. They should not be allowed to own pets. 

All of this is to say that I think it's probably somewhat predictable (and obvious, now that I think about it) that dysfunctional people who treat humans poorly do the same with animals. It's not only lack of empathy, but some sick need to hurt or mistreat other beings.

This is BM to a T. She "collected" dogs just in order to get rid of them after a few months when she found out once again that an animal actually needs care, love and time. They were disposable for her. And that is how she treats humans as well.

When I first picked up the skids together with DH at her place back in the days when the skids still lived with her, poor step dog was locked into the living room and had to piss all over the floor because she could not be bothered to walk him or tell one of the kids to do it. The whole room reeked of piss and the dog looked awful. I often think about that day and that we should have taken sdog with us right there. Luckily, when she lost her kids two years later, she send step dog with them and he lives with us and his two cat sisters now and has our huge garden all to himself.

Yeah, I honestly think people who treat animals badly or even abuse them have to have some type of mental instability or even illness. Otherwise why would you hurt a living creature that cannot defend itself? 

Too bad the abused animals do not rip out the throats of the abusers. On camera, in response to clearly recorded abuse.

Grrrrrr!