So it's slightly complicated set up. My dh is her step dad from previous relationship. But she grew up thinking he was her actual dad. He has always loved her the same. Dsd's mum told dsd the truth after she had split with my now dh. Oh confusing from the start I hear you cry! Please stick with me....
So dh and I have been together for 4 years and recently married. First time dh has been married. So I'm pretty used to step parenting as dh's son lives with us permanently. It's tricky but he knows where he stands with me.
After a mc and 2 yrs of ttc I found out I was pg with our first baby together. I have Dcs from previous marriage. soon after unrelated dh had am argument with dsd and she didn't come to see us for 6 months. She is 15. He couldn't make her as not his biological dd. When baby was born, she came over to stake her claim. I understood the insecurity and welcomed her back into fold. As I do with all dh's children. However I'm beginning to be worn down by the continual verbal battering from dsd. Shes had a go at me about the fact my baby is not in a routine several times. I'm bf as I have with all my dcs although ds has a formula feed if I'm at work. Her mum had a baby 6 months prior to me so this makes dsd the authority on bringing up children. She has opinions on my choice of highchair, my amount of washing, the fact I choose to bf and her mum didn't. I have never slated forums fed babies just defended my position on the proven stats of bf. But tbh it's getting me down..,,I do do thd my rules in my house thing. I am experienced mum of 5 and with dh's ds it makes 6 Dcs in the house full time. Her mum refuses to collect my dss putting her new sons routine first. Dsd isn't even allowed a shower after new baby has gone to bed as it will waken him. It sounds like a military operation!
Last wkd she had a massive go at me as our little ds was crying in the night. None other of our Dcs have ever moaned about this to me. I'd rather he was sleeping too but little ds is a whole floor away from her bedroom so although she may hAve heard him it's not like shes sleeping next to him.
I'm feeling quite worn down by her constant...my mum does it like this...,after 4 years!!!
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Step-parenting
Dsd...can actually be quite a nasty piece of work!
swollowmeup · 27/06/2012 18:47
I know all of this but none of it was my fault! All happened way before I knew dh. I have always tried my best to be welcoming and friendly! I understand it's not ideal but just don't know how to deal with her sometimes. Shes very catty. Dh doesn't want to say anything coz scared of loosing her 
Is it at all possible to turn her criticisms around into 'discussions'?
She is perhaps (badly) trying to have a role in this babies life. Who is essentially a sister to him?
So if she criticises your choice to BF, then (for example) mention a report you had read and ask her her opinion.
Maybe pre empt her by asking her for instance to check the baby's food isn't too hot.
Ask her to research something on the internet for you, even if you already know the answer.
I truly understand your frustration but something on me aches for this young girls sense of where she fits in to things.
I have experienced something similar and it is an awful age any way 
I know that's what she wants! A rise! I really do feel for her as I would never have lied to her in the first place. There was 2 years gap between her mum and dh getting together with me. In that time he never introduced anyone to his Dcs. Her mum on the other hand moved a new man in 3 weeks after dh was told he had to go! There have been 3 men since that I've known of and the new babies father is no longer there now either. Kicked out after he had paid for Xmas this year.
There's nothing I can do about any of that. I have been consistent with all of them. I don't indulge them. I'm very fair I hope. But I find it sooo rude. 
Considering her mum is clearly not perfect by anyone's standards I'm finding it harder and harder to bite my Tongue the more I am made out to be hopeless mother if the year, with a waking baby!
Brdgrl, I say some of those things too to my 16 yr old DSD! 
I too get the "my Mum does this and that" sort of comments insinuating that what I do is wrong 
.
It's a real shame because as time goes on I am more and more likely to simply avoid conversation with her. Her Dad never corrects her on anything for his fear of losing her so I just don't bother to engage with her anymore, actively choosing to be in the opposite room to her. DP moans about her lack of manners and respect as if it's something out of his control .
OP, I think you just have to keep on rebuffing her comments with some similar to Brdgrl suggestions or my favourite when she is asking why I do such and such, is to just say "why not?" and shrug my shoulders. It doesn't drag me into an argument or discussion where I feel I have to defend myself and generally shuts her up because then she might actually have to justify why it is so important I use different cutlery for dinner or make the tea in a different way etc. when we both know it is irrelevant.
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