AIBU to think my boyfriend is too soft with his daughter?

Yes, I agree with you.

She can undo this though. She can move back out and go back to dating.

Several posters have said versions of "run" or "this isn't going to work." If she had just been dating it would have had less impact on the child's life if things go wrong and they split. This is one of many reasons why people should take their time to get to know each other.

Why did the BF agree to this? He is surely more at fault?

Preferably once they have ascertained they have similar values to the things they regard as important. OP has now discovered they do not share similar parenting values which will lead to a difficult future should they have children together.

There's nothing to suggest he is offering limited choices. And this op is someone with specialist Knowledge on child development.

OP, its pretty Common an MN for step parents or those in relationships to get a hard time. I'd be very concerned about this mans priorities and willingness to step up.

I'm not concerned about "most people". The OP is already there. It's a bit like the MN's famous "why did you have a second child with this guy" as if they can magically undo the child's conception. You haven't actually added anything helpful to the discussion.

I think you’re going to end up miserable. You seem to care more about what’s best for her than he does, you’ll drive yourself insane watching him do a shit job and there won’t be anything you can do about it.

I’ve got a 3 year old btw, he’s never seen a tablet, he was bf so hasn’t had bottles but he’s been drinking out of a proper cup or glass for years, he eats what we eat at normal meal times, he tidies up after himself and he’s generally very reasonable and agreeable because he’s parented properly and consistently, as were his older sibling and half siblings. By all means see how you feel in a year but he sounds like a useless parent and you’re going to lose all respect for him. I was a step parent before I had my own fwiw and I respected the job DH was doing with them hugely, if he’d been like yours I’d have run a mile because I wouldn’t have wanted to have my own kids with someone I didn’t respect.

You think it's good for a 3 year old spending her life between 2 homes to also have daddy's girlfriend of about 9 months move in?

Most people don't even introduce the new partner that soon let alone move them in.

It also means the child has OP there when she's meant to be spending time with her dad.

And you don't think it's rushing the relationship at all?

Maybe if OP hadn't rushed moving in she would know she and her boyfriend have different ideas about parenting and she's not keen on his.

Also, clearly your parenting ideas are not aligned so you have your answer there.

What does that have to do with anything? Is there an official guidance on the acceptable moving in date?

Why the heck have you moved in with a boyfriend after less than a year together? Especially one with a child?

So you have to align yourself to his parenting, not the other way around. Because, out of the two of you, he is the parent. When it comes to discussion about your shared children, that's the point at which you two agree how the two of you parent your shared children together.
For the record, I fully support not making the child eat when they are not hungry and to allow them to make a choice of what they want to eat (out of limited options provided by the parent). So, as you can see, we all have different opinions on parenting.
Nobody takes kindly to unsolicited advice about the way they parent. So take his lead on this one and have a conversation about your own when you are ready to TTC.

I genuinely would never live with a man who has young kids because this is such a common issue.

Shes only 3 so her behaviour isn’t going to be perfect but it’s very common for first time parents, especially separated ones to go easier on them.

It’s hard to tell if you’re being too harsh (and perhaps a little jealous) or if she’s genuinely spoiled

No good will come of saying anything though.

Are you living together?
When are you thinking of TTC?

Sounds like the dad should be wary

In general I think I agree but other than the toilet training - which you don't think she was ready for anyway - you haven't given any examples to judge by.

How often are you there? You've only been together a year and he only has her 50% of the time. You don't need to be there much so soon surely? Don't get sucked into stepmum role and make sure they have lots of time just the two of them.

It's not your concern, really, nothing to do with you. If I were you I would carry out a small test to see what he expects of you,, make it very clear you will not be moving in with him and you will only let him stay at yours or you stay at his in the 50% of time when he doesn't have his DD. If he loves you for you he will be happy with this, if he is looking for a nanny with a fanny he will not stick around.

@Boomer55 Total rubbish. The op has actually been very honest and is recognising the issue in that this child is getting mixed messages and poor parenting.

Dad is not parenting effectively and I bet this child is not cooperating with mum as a result. It’s vital parents are on the same page and this dad just isn’t bothering and the Op can see that. It doesn’t take a mum to see the issues here!

I’m a mum but I didn’t give in all the time and of course I recognised the need for potty training methods to be consistent - and did it. This dad isn’t doing it!

I would, op, maybe suggest you help with potty training? Men want 50:50 and then don’t step up. Is this your partner? He might feel potty training is something he cannot do and maybe help from you will be appreciated? Perhaps talk to him about spoiling dd because ultimately this will affect your relationship.

He’s presumably doing 50:50 to save paying mum any money. Is this best for DD? I’d suggest not. Too much time with him is leading to lazy parenting but this would be a red flag for me! He’s not a responsible parent.