There is no way I would allow someone to live under my roof who had accused either me or my husband of abuse. That's just asking for trouble.

Her remarks about your C-section are not the words of a 13yo. Those are the words of an adult - she's parroting her mother. Do you really want BM'S influence in your home?

Finally, make it clear to your husband how much you REALLY want another child and how important it is to you. He denies it's because of his daughter so you want to know the REAL reason for his complete change of mind.  "We're good like that" doesn't explain the about turn and,as he was the one to bring up having another child, he owes you a real explanation.

I had twins at 42 and we considered having one more but came to the decision not to TOGETHER. 

Time to inform him that his failed family progeny will not be living in your marital home in 5ys and that your TWO young children will need his undivided attention since SD has already had her turn being raised.

Keep it simple, make sure DH recognizes that he will be on the hook for a shit ton of CS since.... he will not have failed family minor children still eligiable to take away from his financial obligation to support your TWO young children.

Stop playing games.

Letting SD (BM). Dictate your life, home or anything.  DH must understand his changing his mind will cause his second divorce.
Then if he has any money left.  who is he going to find who doesn't have children, or will want children.

I think you are 100% within your rights and frankly I would be contemplating leaving over letting his child decide if I have another baby. If he changed his mind, for whatever reason, I could understand but SD should have no bearing or even be permitted in the conversation. 

As for the dealing with my husband, since you guys are now making unilateral decisions, I may have to decide that I no longer want to take birth control. He can be responsible for contraception if he wants to prevent pregnancy. I don't want more hormones in my body. 

Your SD should not be making decisions regarding your relationship with her dad.  But... it's entirely possible that your DH was carried away in the flow of having that child.. that he started talking about another one.. but perhaps the reality of actually HAVING that new baby and everything it entailed made him realize that it was more than he really wanted? so.. his daughter's opinions may not have been a factor in why he has appeared to change his mind.  I would be asking for him to be more open about his decision process on this.. 

My youngest SD had issues and it never changed with my first biological son. If it would have been up to her my wife and I would have not had another child, but 9-year-olds don't dictate my life and we had two more and adopted two more because that is what we wanted. This was an issue that we both came to together. 

I will say that my wife always wanted 10 kids and after we had our 9th I told her I did not want anymore. The primary reason is that I want to enjoy my retirement with my wife and to live the last few decades without a child in the house. It is possible your husband overreacted, but it needs to be a serious conversation and not a brush-off. Deciding to stop building your family is something you both need to be in agreement.

Also the abuse allegations.

I am seeing this more and may make a post about it because I simply cannot understand why this is not taken more seriously by biological parents.

To the OP. 

If your husband is not reacting to abuse allegations and brushing it off as teenage issues, then I would be extremely careful in any interaction I had with that SD. When SKs or even other children learn that they do have some power in an accusation they tend to escalate and it can escalate to the point of going to court which means you spend thousands of dollars defending yourself. 

Thing at times but one thing he is adamant about is anything pertaining to bedroom matters (sexlife, having kids etc) is between me and my husband. Skids do not get to meddle, interfere or offer opinions. They don't have a right to an opinion as having kids doesn't involve their uterus or penis.

your sd crossed a line trashtalking you down by criticising you had a csection. Sometimes baby is in a bad condition and drs recommendation is to get bubs out quickly via csection. There is no glory in bragging about a vaginal birth and sd's immaturity right now proves that. Whats not to say when its her time to have kids, she has a csection too and she certainly wouldn't be happy about someone saying the same things to her as she said to you.

as steve harvey said, when you marry, you become a 2 person circle. Anybody else's opinions do not ever matter. Your husband was wrong to take his daughters opinion and use that to now change his mind about having a 2nd kid when he knew plan all along that you both discussed was for 2 kids. So he strung you along and now that has trust issues.

i say hell no to him canning the 2nd kid and now making an executive decision that his daughter will move into your home. So he's in effect canned the idea of a 2nd child to pander to sd and move her into your home so you will be financially responsible for an adult.

apologising doesn't make things ok. He's hoping after stringing you along with the idea of a 2nd kid, that going back on that idea that your love for him will supercede this.

end of the day, kids/teens who lack any real world/life skills do not ever get to dictate what happens in your marriage. Your husband cares more about sd's opinion and feefees over yours, that needs to change. He is giving her so much power and she will use that to control you

OP, has it occurred to you that maybe he doesn't want a second child with you to be sure that there will be a room available for your SD when he decides to move her in?

I wouldnt want a second child with a man who lets a 13 yr old sway his decisions. If that is the case?

He probably doesnt want more because of SD, so that in itself is a huge red flag, as you have pointed out.

You have a mini wife in the making. Unless you want to sister wife it with SD you need to give your DH some clarity. That you and him make the decisions period. 

Blessings

I tried to put myself in OP position when I was dating my wife over 13 years ago.

My wife and I discussed having more children. She wanted more children and I wanted to have my own family. As much as I loved my wife, when I was 28 years old I was pretty clear about that issue.

I wanted three children and she wanted 6 more. Well, we ended up with 5 more, BUT if she would have told me that her tubes were tied or that she did not want any more children I would have probably broken it off back then. I wanted my own family and she wanted the same thing so it worked.

The SD will have her emotions, but what this guy is doing really ticks me off. It is as if he does not care about his wife's emotions. If there were discussions about having multiple children prior to marriage, then you don't just get to change your mind without a discussion. This should be a tough decision and a mutual one. Especially with OP turning 40 she knows her biological clock is ticking.

The more I think about this situation it is just gross to me. 

I love kids, but... I just do not have a major need to have any of  own.

I ended up with an amazing son when my DW agreed to make a life together.  He is mine. All I missed was the delivery room and a bit over a year of diaper duty. I did about a year and a half of diaper duty, hourly nebulizer treatments while he was sleeping,teaching him to read, tie his shoes, ride his bike......

I have no regrets. DW upon occassion would say that she might want an ours baby. I always replied that we have an ours baby.

She nearly died when she was pregnant with SS. Pre-eclampsia/Toxemia that hospitalized her for the last several weeks of her pregnancy. SS was born 5wks pre-mature.  Her Gynos all assertively advised that she not get pregnant again.  We did have a young woman Saudi Gyno who was adamant my DW should have more kids as the one we have is not enough.  

Nope.  I would never jeopardize my bride's life and health for a spawn.  We are loving our empty nester life. We are extremely proud of the son we have raised together.

I have no regrets, I/we have missed nothing.

I get loving kids, I love kids.  I just am neutral on spawn of my "own".

I think it's time you confronted him about his breach of promise. You agreed on a baby before marriage and now he's reneging. You have every right to a full explanation and not just "we're good like that" because you are NOT "good like that". He doesn't get to decide how YOU feel. If your home isn't big enough to accommodate his princess plus a baby then why doesn't he start looking for a place that IS?

How much of a deal-breaker is hit U - turn for you? Ask him how he expects you to trust him about anything important in the future ever again.