This is propaganda, pure and simple. Designed by the parent of an only child to make herself feel better about her choice by collecting countless positive (quantitative) studies to dismiss the negative only-child (qualitative) experiences of Sandler's friends and other interviewees, while debunking supposed stereotypes and replacing them with reasons why everyone should do as the Chinese do: have only one child, and in the process, shaming those that have more. In the end, I feel this is a biased, self-congratulatory piece of questionable value, of which I learned nothing new.Talking about only children right now is highly relevant. Today, there's a continuing trend of having fewer children and there's a rise of only children in developed countries. This is due to high childcare costs, women deciding to have children later, lower fertility rates, the global recession, and economic pressure on families to have two working parents. This topic is in need of discussion so we can figure out how to handle a changing (decreasing) population and work out the advantages or disadvantages of being an only child in the twenty-first century. Sadly, Sandler neglects the disadvantages.The too briefly described research Sandler refers to is troublesome as she relies upon large scale studies, one of which had 13,000 participants, leading me to question how much time was spent with each person, how accurate the data is when individual circumstances tend to be overlooked, and whether the conclusions drawn could be trusted. Few quantifiable results are quoted by Sandler, yet over and over again we're told only children are more intelligent, but when it's revealed this status only adds one to three IQ points, that assertion no longer seems quite so certain when the difference is so minimal. Are the other positive differences she quoted also as minimal?As far as I could tell, none of these overwhelmingly positive studies actually asked the participants how they felt about being an only child, and when the author quoted interviews and asked her only-child friends, unhappy negatives start rearing their ugly heads. Some of the stereotypes Sandler has been aggressively attempting to quash are truisms among them, though she quickly whips out another positive study or two to devalue those cases. Belittling these personal negative experiences and dismissing them with positive research is unforgiveable, no matter how positive her own experiences as an only child, it denotes a lack of respect for others in favour of her own agenda. Sandler neglected to criticise the studies in the same way, which I'd expect if she was evaluating all the research fairly. By taking all of the research into consideration, one could conclude that things like intelligence and self-confidence go up (quantitative studies) while happiness goes down (qualitative interviews).Yes, not all only children are selfish, lonely, spoilt and maladjusted - but some are, there's no point in denying it. And yes, it's more environmentally friendly to have one, and it's glaringly obvious one child will receive more resources like more money, time, space and attention from their parents than having to share with siblings. And they will benefit from those things, although how and how much they benefit will differ according to individual circumstances. However, other factors such as socialising with and being able to relate to their peers is important because spending too much time with adults can alienate them from their peer group. I'd argue attending school isn't enough, as Sandler suggests it is, proximity and access to other children outside school hours is necessary, too. Activities outside the home and exercise are other factors to consider as I'd postulate that those who do these socialise more with a variety of people, rather than with just their parents.On and on, Sandler repeatedly preaches her 'only children are more intelligent and prosperous' mantra, and cherry picks famous onlies and cites the 1979 Chinese One-Child policy for their recent economic improvement to back up her claims, which is more than a little reductive, if you ask me. Really, Sandler's subtitle should be, 'Why You Must Have an Only Child, and Why Being One Can Make You Smart and Successful'. However, upon closer inspection those famous people and Chinese case studies all had pushy parents who provided strict educational schedules for their children lasting from the minute they woke up to bedtime, thereby surpassing the norm for the average child whether they had siblings or not. Most Chinese can't afford more than one child anyway, but rather than just a wish for their child to have it better than themselves, I started to wonder if there was an air of competition between parents to make their child successful, or whether it was to improve their retirement as it's tradition to move in with their child and care for their grandchildren when they reach that age. There's also the enormous pressure on that single child to perform and succeed so they're able to provide for both their parents when the time comes. In any case, you could argue privilege gives these children opportunities to prosper because their parents have clearly invested a substantial amount of time and effort, regardless of finances, and are able to reap the rewards. Full disclosure here, I'm an only child, and one with negative experiences. Sandler would hate me because I don't conform to her views. As one stereotype goes, I was late to walk and talk, but my reading level was years ahead of my peers. Early schooling taught me that being an only set me apart as teachers frequently asked us to talk or write about our siblings and pets - I had neither, and that made me feel like I had and experienced less than everyone else. Despite many children living on my street, they were all a year or more younger though I made the best of it, still experiencing loneliness on the dark, cold, rainy winter days, of which there are many in the UK. Unfortunately, when I was seven we moved 100 miles away to where no children lived near me. Cue more loneliness and a growing preference for the company of older children (usually by several years) and adults. I've never been comfortable with those of a similar age to myself; school was hell - I frequently truanted in my teens, and age 18 onwards my friends have been more than 10 years older than me. I'll also confess that I'm selfish, but only children can hardly claim the monopoly on that trait. And hey, I was spoilt as far as toys, clothes and my mother's attention were concerned. I was lucky.When I think of others I've known who are onlies, most them also had negative experiences for a variety of reasons, but one thing was very clear: they fit into two types. Some were able to cope or be happy in their own company, and others weren't and would do anything to avoid it. Before reading, I had wondered if being an only child meant there was an increased likelihood of becoming an introvert, which would feed into Susan Cain's [b:Quiet: The Power of Introverts in a World That Can't Stop Talking|8520610|Quiet The Power of Introverts in a World That Can't Stop Talking|Susan Cain|http://d.gr-assets.com/books/1328562861s/8520610.jpg|13387396], and because of this I've been comparing the two books. They don't compare. Cain, despite being an introvert, manages to confer balance when discussing her subject matter by acknowledging both positives and negatives of being such, and Sandler as an only child fails in this. Her bias is so pronounced it's impossible to draw parallels when I can't trust her interpretations of her much vaunted sociological studies.A monumentally bad first impression was made after reading the opening chapter. I should've gone with my instincts and discontinued reading then. That chapter was the most biased, one-sided diatribe against negative stereotypes associated with being an only child, never stopping to consider that there may be some truth to them for some or allow for other aspects that, in tandem with being an only child, could produce those stereotypes. Challenging myself to read on was a mistake, and I've struggled to finish. Currently stuck @ 41%. Only children may find they know about most of what is discussed but could find parts of it insulting. Everyone else on the other hand, may find One and Only informative and helpful, or offensive and upsetting if they've chosen to have more than one child themselves.*eARC provided by the publisher in return for an honest review.