Well consider the question from another point of view - why do we treat our friends differently? Because they all have different personalities and have different interests and different ways of looking at things. This affects how we interact with them. When we see ourselves in some aspects of their behaviour we can sometimes have a positive or negative reaction to that behaviour etc. In the same vein, children are all different to each other so therefore our interaction with them will be affected in the same way. Of course there may also be environmental factors such as things they have done or said etc which may colour how we treat them in different ways. And hey I don't have kids and aint planning on it any time soon! lol

My parents treat me and my siblings individually, and in different unique ways, but thats just because were all completely different. I think sometimes it can be good, but when it comes to parents picking favorites, and crap like that.....thats just horrible. There are a lot of reasons that people might do this, such as,....Sex, Age (first or last born), what they have done with their life. I think that all of a parents children should be treated equal, but not necessarily the same.

Different strokes for different folks. Treating each child identically would be ridiculous and ineffective, but do treat them all fairly.

I wont really know the answer until I have children, but different is probably because some of their children may have different needs than another child. My parents in my opinion definitely don't treat us all equally and fair.

I treat my kids differently, because they have different needs. One is self sufficient, can manage on her own very well without any help from me. Another suffers from depression, ADD, and Social Anxiety Disorder, so she needs more from me. I don't actually favor one over the other, but I talk to them differently, as I know one will take whatever I say at face value, while the other will read criticism into almost everything. I love them all the same, and would never treat one like the golden child and diss the others.

there could be many reasons depending on your circumstances but in my case its becuase they like their "youngest child" more

The question is a little vague, it could be interpreted many ways. I assume you mean a person treating his son differently than his daughter or one son differently from another son, whatever the situation may be as far as the number and sex of the children. It's simple, they are different people. It would be strange to treat a boy like a girl or a high schooler like a toddler.

Some of it is based on personality, some is based on need, but all of it is based on love. My son is the most like me and shares many of the same interests, so we like to be together more. My middle daughter is headstrong and though we share some interests, she questions everything and is very abrasive about it, so naturally to avoid conflict our interactions are less than those with my son, and require much more control and patience. If I had a choice of which child of the 3 to take with me to run an errand, she would not be my first choice by instinct, but I would take her out of a need to nurture our relationship. My son may view that as me choosing her over him... expecting me to pick him because we get along so much better. My youngest is sweet, listens, but acts helpless. She will have a cup 1 foot in front of her and ask someone else to get it for her from across the room instead of standing up or leaning forward. She is a little more absent minded than the others forgetting where she put things... like her shoes and socks... but is so small and snuggly (and still young enough to sleep with us on occassion) and is more affectionate than the others. She wears her emotions on her sleeves so to speak. She makes me frustrated sometimes because she'll cry over little things, or I have to remind her to do everything. She gets tired fast and is irritable and whiney when tired. She is also very sensitive to voice tone, and is quick to think you don't like her if you disapprove of something she's done. That's a lot to have to tiptoe around, so the first instinct is to avoid the topics and stick with what you like or what's easy. The part where love comes into play is where you have to consciously spend time and do things with the ones you are least comfortable with in order to break through that comfort level. This can often be misconstrued as favoritism, when in fact it is the opposite and a parent trying to create a better relationship where there is a failing one. My dad says I was his favorite, but I got the least attention. He says he "Never had to worry about me". My brothers are all trouble, always need his help, and he feels responsible for them (as he should), but gives them the attention because they 'need' it. Since I didn't 'need' it, I didn't get it... didn't mean I didn't 'want' the attention though. For the longest time I thought I was out of favor with him, instead I find out that I was his sense of relief. While he was dealing the other's problems, he was comforted knowing that he didn't have to deal with mine because he raised me right.

Because they ARE different.

If you mean why do they treat them differently from other children it's probably because they love them. If you mean why do they treat their children different from each other I think that's because children have different strengths, talents and abilities. While you can set certain standards that apply equally, some kids are going to get better grades others are going to be better at Sports or art or music and really it's best to encourage what they're good at while also helping to strengthen their weaknesses. Also most parents are more strict with their first child and they actually learn as they go to be a better parent. And if the parent has a lot of children sometimes they just get tired and learn to pick their battles and it might seem to the older like it's unfair because the younger gets away with stuff they didn't.