Umm yeah my brothers arent exactly the frosting on the cake....My only child friends are pretty happy they dont have to deal with siblings...But they do say they get bored and lonely so its a matter of opinion! And its fun to play Mariokart with them cause I always win lol.
I have a little brother, and I couldn't imagine life without him. Id be really lonely. I wouldn't have anyone to have a catch with, or skate with. So, in my opinion, kids with siblings are much happier.
I don't know about less happy or not but I know they don't get the unconditional willingness to help your siblings. My mom is an only child and for a while both my brothers were constantly asking me for help for something or another. I of course did what I could to help. My mother told me my brothers were taking advantage of me. I told should the tables be turned they would help me as well. She didn't believe, A few hours later my brother came in and I simply said "I have a problem, Can you help me?" His answer was "Sure, what do you need?" I told him I just have to prove to mom that it all comes around.
I have a brother that isn't even a year younger than me. We are SOO close. I wouldn't be who I am today without him, we are seriously best friends. But I also have two younger twin brothers that get on my nerves. I love them and I also wouldn't be who I am today without them. It's nice to have siblings to share your life with, so I think I'm a lot happier with them that I would be without them.
Only childs tend to be lonely. My cousin is an only child, he's spoiled and all. I know he gets lonely cause he likes to beg me to stay the night. And my uncle, we are all the same age, but like bro and sis.