My partners cousin is obsessed with my baby

OP lives in the real world too and wants to protect her daughter - nobody really knows what’s actually going through the cousin’s mind, or how this might escalate. As it stands, her behaviour and comments are really concerning and I can see why OP would want to distance herself.
If it was allowed to continue and came to an extreme conclusion (kidnap/worse), what would you say to OP then?

You're going to have to go no contact with your partner's cousin. Block her on your phone. She is fixated on your infant in a very inappropriate way and she's trying to establish a quasi parental relationship where she is a primary caregiver who makes decisions regarding your baby. Look how territorial she is with a baby who is not hers.

She's not a parent. She has no rights to your baby. She does not decide anything with regards to your baby and your partner needs to tell her that and shut down her input. If his family continues to encourage this inappropriate behaviour, they can see you a lot less too.

Your partner needs to step up here. This situation could go south in a really bad way. His cousin is using your baby to meet her needs, not acting in the best interests of your baby.

@Mummyme12345 she can message whoever has the baby but she’s the one who will look mad for telling them she should have her? I was going to say let her crack on, but this looks to be a more serious issue ‘with her’ now you’ve mentioned this …

Ignore her messages, grey rock her. Please google grey rock techniques. You need to advocate for your baby and stand up for her. Damn the wider family and what they think. It's not their baby. Once you stop the cousin spending so much time with the baby, you don't have to answer all these questions. She's a 19 year old, you're the adult so you have to be the adult. You have a baby so protect her.

Please do NOT buy her a puppy!!! Get her one of those plastic babies!

Anyone who called me dishonest or rude would not be looking after my baby

She's an oddball, and very much a Red Flag. Don't let her look after the baby again ever...

Edit:Typo.

I think you are minimising your DH role in failing to solve this.

OH mentioned to her mum that she’s getting too much but it all gets turned to me being a sensitive sally so I’m a bit stuck
So when you DH talked to his mum about his cousin, somehow your name got mentioned and you got the blame? Why would your DH mention you? Or if his mum mentioned you first, why didn't your DH shut that down and re-focus the conversation on the cousin's behaviour?
And how come you know the detail of this conversation - did DH tell you afterwards that his mum thinks you are being a sensitive sally? Is that helpful?

I get told often that I don’t understand his family or their humour
Is it your DH telling you this?

Basically, your DH does not have your back, he is failing to stand up for you and is instead letting the blame fall on you so that he is off the hook.

She wasn’t offered your baby! Your DC isn’t a shared toy or resource to be passed around. You need ( and your DP ) to establish firm boundaries.

Where you are, what you are doing, and who is looking after your DC is NOTHING to do with her. Stop telling her anything, it’s not rude or dishonest, she is the one who is being rude. If you’re not usually so assertive, toughen up. It will get easier, and save you so much stress going forward.

Taking some time with your DC seems like a plan, but get boundaries in place as you go, don’t wait until you need childcare again, or it will continue. You may need similar boundaries with others as they appear to be enabling/encouraging her. She is a CF.

If a man was behaving like this, people would be saying it's a red flag for potential child abuse.

It's less common in women, but it's far from impossible.

This looks like grooming to me, especially with the weird family backing her up.

Her husband doesn't properly have your back as he's clearly there presenting it as YOU having an issue with the cousin whereas it should be WE - a united front, especially as he appears to be able to see the problem clearly.

I would keep your child away from her.

Also let her know that any further harassment of this nature will result in her not being invited to the christening at all. Christening is for people supporting the parents, not anyone with delusions about them parenting. Anyone who wishes to cause drama in support of these delusions can also stay home.

It’s a happy day with your DP and LO. You don’t need to be distracted or managing tantrums at this cousin seeing someone else sworn in as god parent.

”This is just your hormones”
”DP and I are happy in our joint boundaries”

I repeat what I said before- you need to source proper professional childcare.

Nailed it. She's only your partner's cousin anyway, that's not close family, zero obligations. A

Don’t even respond! In fact, block her. Leave the family to drama themselves into oblivion and ignore it all. Let your DP deal with them and he can stress that this cousin clearly has boundary issues and maybe gently say she needs MH support. She does NOT need access to or information on your child and you absolutely need to be firm at this stage and make your own boundaries.

At this stage you would be unreasonable to leave the child in her care ever again, as you would be encouraging this ridiculous fantasy that your LO is in any way, shape, form or even small part “hers”

”when you die she will be my baby”. So she's thought about you dying
while your daughter is still a baby. That's chilling. You should tell her so.

She sounds obsessed and unhinged.

The only way to deal with crazy is to out-crazy them.

"Who the absolute fuck do you think you are Betty? DD is my baby, not yours, you don't have a say in what she does or where she goes, you are not nor will you ever be her parent."

Rest of the family be damned. This is absolutely insane and threatening behaviour.

Wow £68 for a cousin four hours in the evening twice a week is extortionate! No wonder she enjoys it. She is being weird though so I’d find alternative arrangements!

Hard to believe this has been allowed to become such an issue but the whole family sounds a bit mad so it may have been a boiled frog situation.

Well done for posting, well done for taking feedback on board and making some changes. You know this girl is beyond inappropriate so stop letting her have your baby at all, stop replying to her interrogations and stop engaging with other relatives trying to undermine you, when it comes to mad cousin or anything else around your baby, your parenting and your childcare arrangements.

She has absolutely no right to see your child, to babysit, or to know where your child is and with whom. Tell her clearly then block all future texts. Same with other family members if they try to intervene. No discussion.
Sadly, although I appreciate that it will cause ructions, she has to be told quite clearly that this behaviour has to stop. She is likely to go into meltdown so the advice of keeping your door locked is good. The worst that can happen if she turns up is that she causes such a disturbance that someone calls the Police. Keep all the texts from her and other family members as proof there is a problem.
I would never let this girl babysit again or be in a situation where she is alone with the baby. I wouldn't let any of her family babysit just in case ' they know better' and leave her alone with the baby.
The girl sounds increasingly unhinged and your primary duty of care
is to your baby not to family members. It may be worth having a chat with a health visitor so that an 'outsider' is aware of the situation.
It won't be easy but has to be dealt with head on.

She sounds mental. What sort of drama does she cause when others are planned to look after baby?

This is weird. You need to draw firm boundaries with her AND with your family. Stop leaving her alone with your baby and don't allow her to provide childcare, and be honest that you think her attachment is unhealthy and not a normal aunty-niece relationship. If your family get involved, tell them that your choices are not up for debate and you don't care to discuss it anymore.

no don't do this its not kind to the puppy

She's not a stranger so I doubt anything bad will happen.

Hollow laugh .

Op this girl is deluded, having your baby around her so often is only feeding her obsession.

This is quite bizarre behaviour

Speak to your husband, if he says it's a you problem and you are being sensitive, tell him clearly & calmly that it is your cousin and her behaviour that is the issue.
Tell him what she has said, repeat that this is not normal to say these things. She is being enabled by her family & your husband so make it clear you expect his support.
Then arrange alternative childcare, only let her see your child when you are there. She needs to have some boundaries in place and fast.
You don't need to explain your childcare details to her, or give details of where you are and what you are doing. This is your child, your life.

Her comments, the more I think about them, and the over involvement in your child's life I think are quite worrying. If reduced contact doesn't stop the comments and the overbearing behaviour, then I would see if this is something she needs outside help with. It might sound dramatic over some 'harmless' comments, but this behaviour sounds obsessive and she may need some support from someone to help her see it isn't healthy - especially if her family don't see an issue and don't or won't speak with her.
.

You and your partner both need boundaries...and a backbone.

Why are you letting this teenager get away with this?