To not give up my Playmobil and cut cousins hands off if she tries to take it?

[Qantaqa]

Ok Ok .. the last part is possibly U....

I have an extensive collection of playmobil which has been boxed up for many years. I briefly got it out 10 years ago when my DSs were 7/8ish but after a particularly traumatising incident where they broke some I boxed it all back up and put it away and never got it back out. I say this to show that my attachment to it is frankly ridiculous.

My cousins daughter is 6. She is in many ways an mini version of me at that age and I adore her and obviously indulge her and am silly with her in ways her parents can't be. I (obviously) have been buying her Playmobil for birthdays and Xmas which she loves. My collection came up in a discussion at a birthday meal recently and cousins daughter asked if she could come over and play. I said it was boxed away and that was it.

Except it isn't. Cousin has asked about "getting some sets for her DC since I aren't using it". I've politely said various versions of no with excuses, but this morning I had this message,

Hey Q. Any more thoughts over the Playmobile? DC is beside herself with excitement ay the thought of having some of yours! We are out for Mothers Day this afternoon but I'll give you a bell later. xx

Clearly I need a stronger "No over my dead body" response but having moaned mentioned this to DM at lunch she thinks IABU to not "pass it down".

DB thinks I should just go buy a box off Facebook and hand that over which I am considering.

So AIBU to want to keep my Playmobil?

[Stewball01]

YANBU. I am 78 and I still have my doll's cot. My dd played with it but I didn't pass it to my dgd as I knew I'd not get it back. DiL would have passed it to her sisters. They're not my family.
I quite understand you. Either the Will comment which is very good or be tough and say 'no again' I told you no once. That's enough. Good luck.

[Stewball01]

@JudgeRudy
Wonderful. Let her know she's fucked up with dc.who is a little girl and trusts her mum wouldn't hurt her.

[JudgeRudy]

@Stewball01
I'd be very blunt. I'd message her in such a way as to get 2 points across.Firstly - its not happening Secondly - cousin will be upset and its your fault.
Say l can't believe you've told cousin that when I distinctly said NO, it's not happening. Why would you do that to her. She's gonna be so hurt when you tell her you've made a big mistake.

Not wonderful at all, but yes, let her know. The mum has fucked up big time! She has indeed hurt her child. She probably knows this now, but in case she doesn't there it is. It also quite rightly shows that OP is not going to be emotionally manipulated and takes no responsibility for the mums mistake.......or I guess a simple no could do with no explanation but communication seems key here so after thought and consideration lm still happy with my suggestion (or words to that effect).
Which bit did you object to and how do you think they should have responded?