Perhaps the most apparent disadvantage of being an only child is the feeling of loneliness - not having a sibling to play with regularly and to be able to share your thoughts and memories with. When you parents are no longer around, not having a sibling to talk about things with or look up to for any kind of help or support can be quite a disadvantage. Also, when you parents get older, being an only child, you would have to shoulder the responsibility of taking care of your parents on your own, which might be overwhelming.