[quote Elisemum]@WithANameLikeDaniCalifornia yes it is selfish. Children grow better with a sibling, they have better, more fun childhood, they have each other as friends, they play with each other and have someone else to relay on in life when parents are gone:(. Its obvious and the truth. It’s not negotiable really and it’s been proven.
Whether you want to have one or more- up to each individual but having only one child (when you could have 2) is selfish as parents obviously chose their own well being first ahead of their child… I’m the only child and I had amazing childhood but always wished I had a sibling. I cannot wait to see my 2 boys being best friends and doing everything together, standing up for each other and go together through life! That’s what’s life is about[/quote]
@Elisemum Just wanted to ask if you have ever considered that when a parent chooses to have one child for the sake of their own well-being they are doing this also for the benefit of their child (and their partner)? Happy parent = happy child, and all that? I have a 9 month old DD who is my world and I am seriously doubting whether I should have another. This is because I struggle with my mental health (anxiety, OCD, depression and, I suspect, executive dysfunction) which makes parenting just one child (even one who sleeps and feeds well, and has no health issues) very challenging. Despite my issues, I give my all to looking after my DD and I feel like I have a better shot at being a decent mother if I stop with her. I feel I could become one very stressed out, frazzled and shouty mother to two or more, which would be no good thing for those children or for my lovely DH. I actually feel that having another would be a selfish move on my part, something done only to conform to the popular view that two children makes a ‘proper family’ 
I’m not an only child - I have a younger brother and a younger sister. I love them both, but once we reached the teen years we grew further and further apart. We have nothing in common and we don’t enhance one another’s lives. I think because there were three of us, it was very much expected that we spend all our time out of school playing with one another and entertaining ourselves, and my parents only had so much time and attention they could give to each of us. I can’t remember doing much in the way of extra curricular activities or having much encouragement to pursue my interests. As a teen and adult, I have struggled with my mental health and also in forming any lasting friendships and have felt very lonely as a result. So no, having siblings does not automatically mean your life will be better. I know of only children who seem far happier and are more well-adjusted than myself.
As previous posters have pointed out, you have no idea what sort of relationship your boys will have as they grow. Hopefully they will be close but it is naive to assume they will be. Just read the many threads on here about siblings who have fallen out and hate one another!
Hopefully that’s given you some food for thought. The OP has every right to stick with one child if she feels that is best for her family. There is nothing selfish about it whatsoever.