it’s perfectly normal for feelings towards stepkids to change once you have had a bio child together, as indeed it is normal to feel differently about parents, partners and friends. It’s partially biologically driven ‘protect your offspring mode’. You shouldn’t need to tolerate from other people more than you have to. There’s nothing thing like a spoilt stepkid to amplify these feelings, - this will get easier as time goes by. Also, it is sometimes easier connecting with smaller children I found that with my bio kids. They go a bit quiet approaching the teen years, a few years after that they get all moody, then 19\20 you end up with a perfectly nice adult who understands what reason is. 

When I first met my DH his children were about 15, 12, 10... the 15 yr old was annoying but the other two were precious. I used to spend lots of time w the youngest girl doing homework, baking, etc. 

I dont see you say anything bad about the 6 yr old kid besides being spoiled and entitled. most are, even my BK were at that age lol.

I think you should give the little kid a chance and show him love and kindness. He is young maybe you can make the difference we havent been able to in our adult skids.

you only have him four days a month.  He will not get unspoiled, to many adults are there to. Spoiler him. You have to have a talk with DH to make reasonable rules for your home for SS.  As he gets older, hopefully he will get friends and will not want to come over. 

Your feelings are valid and normal, though I think slightly misplaced.  Your SS is 9, it's not his fault that the BM plays these manipulative games & spoils her son.  Does it make him difficult to be around?  Yes, absolutely, but it doesn't make it his fault.

I understand though, our BM is a nasty, lazy, crap parent who doesn't know what discipline is and spoils the kids rotten.  They can be lovely & sweet, but omg spoiled brats at times too who've got no concept of respect or money. It's frustrating, and I lose patience at times as well, but do keep in mind that, at 6 & 10, it's genuinely not their fault.

I also understand the repulsed feeling you're describing, I felt this way when I was pregnant with our baby and it was horrible.  I thought I'd want them to feel the baby kick, but I didn't want them touching my tummy.  I didn't like it when people commented on how 'great of big brothers they'll be' and how 'lucky' my BK was to have such 'great big brothers'.  I always smiled & said 'yeah it's wonderful!', meanwhile internally I was screaming 'I don't want my kid to be anything like them!!'.  A lot of it was hormones and it's calmed down a lot lately (thank god).

I agree with the others who've said you should treat your SS kindly, but anythign beyond being civil, polite and kind really isn't necessary.  Let your DH take full responsibility for his son, disengage from any parenting and focus instead on your DD.  I do think you should look into why you're having such an intense triggering reaction to him though, that's not a healthy thing to experience and your mental health will improve significantly if you can sort that out.

Take care of yourself, make sure you get some time away when SS is around (which is good for your DH to have 1:1 time with his kid anyways), and ignore anyone who's telling you you're selfish for feeling the way you do.  Your feelings are your feelings, and, unless they've been in your shoes, they really have no grounds to comment on what you're experiencing.  I never thought my feelings for my SS's would change as much as they did when I was pregnant with my child.  It caught me completely off-guard, and took a ton of soul searching to understand.  Being a SP is one of the hardest things ever, make sure you're making yourself a priority & looking after yourself as best you possibly can.

Yes, I totally get this. While we don't have our own kids yet, I wouldn't be surprised if I felt the same as you after having our own. I think at lot of it (at least for me) is resentment over all these situations we *weren't* supposed to have to deal with in a "normal" relationship - we shouldn't have had to worry about being 2nd, our child shouldn't have had to worry about being 2nd, we shouldn't be having all these extra arguments about someone else's child affecting *our* relationship...but we found ourselves in this situation bc we chose to be with someone with a kid (a seemingly simple decision that ended up coming with SO MUCH BAGGAGE), so it's easy blame everything wrong on the SK's existence.

I haven't figured out how to like my stepkid more, but I do find that it's much easier to tolerate her (and all the other baggage) the more connected I feel with her father. If her father and I are doing well, super happy, then I don't really care what she's doing or how she's annoying me, lol And at the end of the day, the relationship with her father is what I wanted, and me and her just have to be respectful and courteous of each other.

Has anyone dealt with their husband having a manipulative ex wife that continuously uses the kids as pawns to get what she wants and your husband continues to give in to avoid conflict which impacts your relationship?  I give my all to the kids and him. When he brings up doing something with the ex and the kids without me I feel hurt. I do as much or more for the kids than their BM. I feel like I should step back and be less involved if he is even thinking about doing things without me because of her. We are a blended family now. I should not be excluded if I care for those kids the same way I would care for them if I was their biological mother. It hurts and it is frustrating. I have never spoke against her to the kids and she is not cordial enough to say hi to me when I take them shopping for presents for her. Instead she tells the kids not to be friends with me.