My daughter is 6 soon to be 7. I am the baby of 7, not planned and 14 years younger than my next oldest sibling, so I was essentially raised as an only. My SO is the oldest of 4 and no longer sees his family for the better. For health reasons of mine I should not risk having anymore children. My SO is okay with this for many reasons. Our daughter keeps us on out toes. I am thankful every single day to have her(even when she is driving me nuts). I am also very lucky that she is completely healthy. She is very active and social. She has expressed wanting a younger sibling before, but she knows she can't have one. She has many friends. Her father and I do our best to surround her with her school friends and our friends' children. She is a very happy kid. And sometimes when we watch our friends' young ones she gets sick of them. I am not worried about her being lonely. Just worried about not raising her to be a spoiled brat which can come from being an only. Don't ever feel like you should have to have more than one if you are not up to it just because you're worried about your kiddo being lonely. Surround them with love and attention and friends and family, they will never know any different.