AIBU to think my son-in law is mean to deny my daughter the 3rd child she would love.

Hi again Kandinsky. Sorry that sounded harsh. I can see you are only expressing how you feel. We all feel sad about lots of things. I sympathise xxx

Yes YABU
Not least because it does not concern you
Couples should decide on the size of their family jointly
In the current economic climate it makes sense anyway to choose the size of family you can afford . Bringing up a family is expensive and who’s to say what the future holds.
It certainly not “down to the woman” !

Really not your business. It's not a given that a 3rd child would be healthy anyway. The decisions about family size are complex and specific to the couple. Definitely not the woman's sole decision if they are a couple! The father isnt just a speem donor and has the right to bring the children up, pay for their needs and be fully engaged. Stay out of it completely

This can only be agreed by the parents and no one else, it is their business.

Can I just say I am not getting involved and would definitely not say anything.
But when my daughter tells me she’d love another child ( and she really would ) but ‘he’ says no, I can’t help but feel sad for her.

Nothing to do with you I would say

No the number of children a couple have should not be down to the woman. It must be a joint decision based on what is best for the two of them. Clearly finances and practicalities need to be looked at can they afford another child, do both Parents care for the children or is it mainly down to the Woman. If down to the Woman has she though about what extra she will be taking on. Does she work, does He take joint responsibility for household chores and cooking etc. So much to think about before embarking on having another child.

No, I think it's definitely something on which both the mother and father need to be in agreement about. And it's definitely NOT something in which you should be getting involved.

This is something you need to stay "Mum" about.

Dont get involved for sure they must work it out for themselves, my youngest daughter had 3 children then after 2 yrs wanted another. Not typical for sure but she is a super mum who just copes with everything.

This is a difficult one but it is not a situation you should voice or even have an opinion on.Your son in law is acting responsibly and sensibly and the decision should be their joint one.

Surely it should be a joint decision and for the couple only.

Oh dear, hope they can come to a place of agreement.

Sorry, I don’t agree, both couples need to agree on how large their family should be.

How old are the two they have already?

I think is obviously a joint decision and definitely not one you should share any opinion on with either of them. I think you SiL has a point but can understand your daughter wanting another child. Neither of them should browbeat the other into making a decision they are no fully onboard with. Having a child is hard enough when both parents want it.

I disagree with you. I don't think he's being mean and I don't think the decision should just be your daughter's. But I definitely don't think you should get involved.