Bully child in the family is preventing DS from bonding with his grandparents.

I think you are right not to leave your child with them at the moment. Have the PILs to stay with you for a weekend instead.

Your child is 1 and it sounds like you can't trust the adults who would be in charge to take care of him properly. I don't think you should be in a dilemma about this, the answer for me would be a definite no. When both kids are older you can revisit it, the 3 year old may well be better behaved and your child will be better able to deal with their behaviour/stand up for themselves. The will also be able to tell you if they enjoyed at their grandparents.

I definitely think some 3 year olds kind of "try out" being mean and pushing around younger/smaller kids. It doesn't mean they're going to grow up horrid of course, it's kind of a normal part of development for some kids. But they definitely need watching like a hawk around smaller kids and the behaviour needs correcting so they learn what is acceptable.

I definitely wouldn't leave a 1 year old in the same place as a "pushy" 3 year old unless the adults are going to be supervising really closely. It could lead to a nasty injury. In fact I wouldn't leave a mobile toddler with anyone unless they're capable of supervising really closely, even without the 3 year old. You need eyes in the back of your head at that stage and grandparents can sometimes forget this!

There's plenty of time for him to stay with his grandparents when he's a bit bigger.

A 3 year old might be approaching 4. Yes they can be little bullies. Anyone saying otherwise hasn’t spent enough time around enough children to see that.

Regardless, he’s shoving a one year old around with no consequences so I wouldn’t put my child in that position either.

I think some posters have been quite harsh calling you precious. I like to think I'm quite relaxed. I had a weekend away leaving DH and MIL with a 2yo and 9mo to look after, and I wave MIL off for days out with the kids with a cheery "have fun I trust you and grandparents are there to do the fun bits" but I wouldn't let a 1yo go to grandparents for a whole weekend, even without the boisterous 3yo in the mix.
I agree 3yos aren't bullies, but 3 is all about pushing boundaries and working out acceptable behaviour. If my 3yo is round a baby / small toddler I have to watch him like a hawk, constantly remind him to be kind and am prepared to have to remove him if necessary.
Can you sell it that your house is all set up babyproofed, familiar etc and invite them there for you and DH to have a wekeend off (day out, night out, lie in) while they look after the baby?
Its great that you want to foster such a good relationship, but your fond memories will be from when you were older, the groundwork for extended time with grandparents can be put in now but it doesnt need to be whole weekends with them at 1yo.

There is a big gap between 3 and 1.

At this stage, the older one may need a lot of intervention from adults to teach them to behave appropriately. If thats not happening you may want to delay the weekend away.

You're getting a hard time on this thread because people dont like the way you've phrased your OP. Of course your is quite clear, that's just mumsnet for you.

You have no idea how you’ll behave in two years time 🫣 maybe you’ll be absolutely desperate for a break with a younger baby and more than happy to leave him with family.

Well everyone can waffle on about whether or not a 3 year old can be a bully or that you’re being precious, but I wouldn’t allow my 1 year old around the irn bru guzzling, iPad watching, baby shoving little nyaff either OP. Not without my being there. No chance.

Kids grow up and change but at the moment he’s hitting and shoving a one year old with no consequences from the adults, so it’s a no from me.

Why would you judge a 3 year old like this??? I have a 3 yr old ds and that's normal behaviour!!!

A lot of people are stepping up to defend the 3 year old, but I have a cousin a similar age to me, and she is a bully and she has always been a bully.

I remember going to our grandparents as a child and she would be a really antagonising child and I would often come home so worked up in tears and sob myself to sleep. Yes, even at 3.

She would launch heavy hard back books at my head, she would steal, she even tied me to the washing line post once with the dogs chain, she would push me down stairs, if I said I needed the bathroom she would rush up stairs and say she needed the bathroom first and then faff around until I wet myself and she knew what she was doing. I have a photo of us, aged 3, 3 and 5 with her, me, and my older cousin, sat on the stairs and she had just yanked my hair so the photo caught them both sniggering and me bawling my eyes out. She tried to drown me in the bath.

My grandparents way of dealing with it is sticking us all on the sofa, telling us all to shut up, and my grandad asking her what she would like to watch on TV.

So I do think 3 year olds can be little bullies. And if you were my mum I wouldn't want you to leave me there either.

They don’t have the capacity at three to be bullies.

TBF far too many people are hung up on you calling this child a bully and whether that's fair. It probably isn't, but also has no relevance to this thread. Obvious you are not an AH to not leave your son in the presence of an older child who might torment and hurt him with adults who won't prevent it happening.

Wait until your own child is 3

The child is 3 and your child may well behave the same at 3 as a lot of 3 year olds are boisterous.

However the issue is the child's behaviour isn't being corrected so on that basis alone I wouldn't allow it. Grandparents who dont correct very rough behaviour, allow ipads when they should be dealing with poor behaviour and hand out lots of junk food are a no to me.

Had to read quite far into the thread to find out the age of your child which I think is essential. I would say he’s too young in this circumstance. In a years time when he’s fully confident on his feet and can communicate and his cousin is 4 it will be much more appropriate.
in the meantime I would try to spend more time with the gps and cousin with you there in preparation of a solo visit age 2

1 is, in my world, way too young for a sleepover without a parent.

Yes, some of them most certainly are.

No I wouldnt allow it. Not a one year old child who cant defend themselves.
Three year olds can be extremely hard work and need firm boundaries . They have to be monitored very closely at that age.
Don't inflict this on your baby

I agree with other PP that a 3yo isn't a bully but I recognise the behaviours you describe.

I think this can be normal behaviour for a 3yo, however, some children seem to behave this way a lot of the time and are allowed for it to go unchecked. My 3yo has his moments but he's generally good at playing nicely with others - he's never rough, but we may sometimes need to remind him to share.

I would actually be more concerned that they're appeasing him with fizzy sweets and iPads.

I spent lots of time with my grandparents as a child and my son gets 121 time with his, including two long weekends so far, but I think 1 is a little young to need a solo weekend to bond with his. That's very much a parental choice, but it sounds like you're not convinced it's a good idea so not sure you need to force it.

If I were you, I wouldn’t be too quick to refer to a 3yo as a mean bully when your child is only one and hasn’t reached that age yet.

I also wouldn’t send a 1yo away for the weekend without building up to it first.

I don’t think a 3 year old can really be a bully or be mean. But they can have a huge amount of energy and are likely trying to work out boundaries, emotional regulation etc. That’s where the adults come in. Or not.
You do sound a bit judgmental and it’d be worth reflecting on the words you use re this child: bully, mean, not normal. Your experience with your DC is not going to be exactly the same as others.
That said, if you don’t feel comfortable- and that is fair enough- then maybe wait until your child is older.
Finally, re GP generally, this can be tricky as they may wish to indulge the GC and do so by giving what they see as ‘treats’ like sweets etc. Certainly my mum would give my DD chocolate while at the same time telling me it’s important kids don’t have too much sugar. Just flagging as something to navigate!

Do you mean a sit in walker or a push along one. If its a sit in - this is one of the reasons which they aren't safe - off topic I know - can be tipped, pushed off steps, and terrible for their hip joints.

Can your DH do and stay with his parents with DS? Or you could invite them to yours

As you say, it's he lack of boundaries and adult behaviours which are an issue- giving sweets and fizzy drinks, not managing his behaviour. Children often don't know what is and is not ok unless they are taught

You son is only one.
He is very young.
Gradually ease him into time with GP.

Request that GP have DS1 to stay, first off, for a half day on his own, including a meal.
Then have him to stay on his own for a whole day with two meals.
When you are all confident that DS1 is secure and coping send him for a some whole days when DC3 is visiting.

Only progress to your son staying for the night when you know that he is comfortable being there. That might be when he is three or four and after DGP have learned DS1's bedtime routine when they help at your home..

DC3 will soon grow out of the 'sun shines for me' stage and he'll be co-operatively playing with more consideration before he goes to school.
Adults in his life could be steering his kindness and manners more though.

Bully in the wrong term though - self centred behaviour is perfectly normal at 3 and is a stage of development the way the 3 year old is normal

the failure here seems to be the parents and grandparents guiding and teaching about empathy and sharing etc and how we interact with the world

or they are and the OP is being precious about her 1 year old

either way the OP isn’t ready for this to happen and @browser2025 neither should you be - weekends away from you are a parenting choice and not a necessity. You aren’t ready your child is too young to ask so bench it

abd stop seeing him as anything other than a 3 year old. Even DD who at 16 has never had any form of trouble at school had a couple of moments at 3 and DS was bloody awful