To not want involved in babysitting my nephew

YANBU, you did not volunteer for this, your parents did.

i know exactly what you mean. In my case its MIL visiting and then bringing over SIL's DS! its a very delicate situation and rather unfair of your parents to expect you to just "run" with it. Can you not have a frank chat with your parents and just say, you love having nephew over but on planned days, rather than impromtu visits as you are somewhat tired.

Failing that, when they bring him over, dont do anything for him until you're asked then you can say "mum, you're the one babysitting him" perhaps they will get the message then.

I agree, it's not your responsibility to take care of her child. Personally I think asking/expecting family to step in as child minder is asking for trouble. Sooner or later someone feels that they are being taken for granted or overstepping the mark.

Single parent here of one toddler whose aunt has never babysat, She didn't have him so she isn't obliged to care for him. (However all offers are always gratefully appreciated ).

YANBU something should be said sooner rather than later though because it could very easily become a habit and expected

Go out every time they come.

I wonder if they regret offering and she is finding it too much.

At anyrate, you will have to say something or she won't know to stop...

I can understand why your parents don't want to stay at your DSis's and mind there, but they have flipped it around, and you are evidently struggling.

Using language like "struggling to keep up" and "knew you couldn't take DN on, which is why you didn't offer in the first place" might help remind them that you have responsibilities, too.

Could you compromise on "popping round" there during the day, so they aren't alone all day there? Or "playdates" at yours, before concrete events like supper?

I agree with LaWeasel.

It's a massive commitment to take on, and it sounds as though they felt pressurised into it, and are now trying to make it bearable by off loading on to you.

You don't mention your children's ages, though I'm guessing fairly young as you're at home, so perhaps another reason in their minds is that it's nice for your nephew to have other children around (or a child friendly house with toys at least!)

And therein lies part of the problem. They probably realise that two (possibly elderly) grandparents are not necessarily the best form of childcare for a young child. It may be that your nephew would be thriving with a cm who had other youngsters, or at nursery.

Whatever the reasons, I think you're going to have to be quite tough, and make your feelings known and just be unavailable. Perhaps have a word with your sister too, to make it clear that you aren't prepared to take on this responsibility. It could be that she's kind of complicit in it too - realising your parents aren't really coping, so happy to see them come round and off load on you. She needs to make proper childcare arrangements for while she's working. Family and regular childcare are usually not a good mix - people feel taken for granted and aren't allowed to just build the natural relationship they'd have without strings attached.

I have a rule on my work days which is that I organise paid or grandparent childcare, and the grandparents are second option as they tire easily and have commitments. I am financially benefitting fron the work and don't therefore as a routine thing exoect that others should help. I will ask others to help if childcare falls through. I would probably feel a bit cheesed off if I thought i was being used by someone else as an alternative to paid childcare. This has started to happen sometimes and i wasn't happy about it. You have chosen or been placed in a situation where you are looking after your children instead of paid work and as such shouldn't have to regularly prop up your relations. Your parents have a similar choice and are forcing you to be part of that choice. Occasionally, fine. Not fair all the time.

OP have you given any indication to them that you arent happy with the situation. The grandparents may well just assume that you are fine with it all esp if you just get on with playing with /feeding your nephew. You need to say something - maybe some sort of compromise that you are happy to have him over one day a week/fortnight or whatever.

Hmm, of course YANBU but it's going to cause upset to say so. I think in your shoes I would go with what a previous poster suggested. "Mum, when are you feeding DN so that I can make sure I'm out of the kitchen for you" etc. Oh, and I would go out for appointments ( so not fun things for DN to come along to) a fair bit. If they can't cope they need to tell DSis and if they don't want to cope, well that's their problem too.

Why are your parents staying with you if they are babysitting your nephew. Why arent they staying with your sister.

This surely isnt a long term solution as you say they are 'visiting' so how long is this arrangement for.

I think you have to be blunt with them - they may have made this commitment to your sister but you haven't and they are not welcome every day.

YANBU.
My in-laws look after my nephew, they have him one day a week and one overnight stay.
A few months ago, they suggested coming to visit us, bringing him with them. Then getting him to sleep over here, and going to stay in a hotel! (Nephew is 3, not a good sleeper, not potty trained yet).

I said no. So should you!

My mum and dad have come to visit as they live a distance away from us and are staying with me. This is allowing them to be available to watch my nephew. - I don't understand, i'm sorry if i'm being thick but is this a temporary thing or do they live with you full time?

Sorry quick re-read, I see they don't live with you, is the babysitting situation temporary? I agree with other posters, your mum does seem a little overwhelmed and if it is a temporary situation maybe she hopes you will volunteer to take over? I think you will have to address this head on, it's not fair on you.

My old roommate did this, I had to finally tell her she was the one hired, not me. She actually quit the job, as I wouldn't change and feed the baby for her, and she claimed she couldn't do it, as she was pregnant and couldn't "handle smells".
I suggest you are honest and ask her to do the childcare at the child's house, as arranged.

you need to either talk about it with them (sister/mum/dad) and say you need more time for your own children and please can they pop over less OR you arrange to go out when they arrive - see friends in thier houses for coffee/toddler groups/library visits etc ..