Unless there's some extreme situations (financial, health etc)---your cousins are the biggest jahils for having only 1 kid.
Never have 1 kid. Have atleast two. Kids who are born alone grow up without a sibiling experience. They don't develop mentally. They don't experience the love, fights, jealousy, competition etc with their siblings (for small things such as getting more candies even haha).
This sibling experience is fundamental to a child's growth mentally. I have seen many people who are psychologically off---and were only kid in their household. Imagine the loneliness they felt all those years!!
(Before anybody brings their dumb ideas: If ENTIRE culture is prone to having 1 kids only--such as China--this changes the equation all together since all kids have similar experience. However, in a family oriented culture like Pakistan--where one kid is alone while all/most of his age-mates have their siblings--single kids develop loneliness inside them as their childhood experiences do not match their surrounding that they see/experience around them).
So please, don't be that cruel to your child. Always plan to have two/three children atleast, when the time comes.
Btw, I don't care about Pakistan's population. It very well can be 199 million. Who cares? I was just saying that lets not post dumb posts and wait for the final results of census.