Q. Are they identical?
A. No. They do resemble one another, but our twins are boy-girl, so they are fraternal.
The questions behind the question: "Does looking alike equal 'identical' twins?" "What is the true meaning of 'identical' twins?" Identical twins share the same genetic DNA makeup. Subsequently, identical twins are the same sex. (A worldwide total of three cases have been documented in which one of gestating identical boy twins "lost" a Y-chromosome; in essence, creating a girl who lacks the usual second X-chromosome. The cases of this occurrence are so rare; it is statistically accurate to say identical twins are of the same sex.)
Q. Why don't you dress them alike? (Or: Why do you dress them alike?)
A. For the occasional holiday or photo opportunity, I'll coordinate their attire. To dress our children alike every day is more effort than I need to add to my plate ... especially in the early days when errant spit-up or diaper malfunctions force frequent wardrobe changes.
The questions behind the question: "Do you have concerns about their individuality?" My feeling is that the vast majority of twin parents are hyper-attuned to the fact that their twins are often viewed as a singular unit. Whether you elect to dress your twins alike or not, do everything you can to reinforce their individual personality differences. Despite the old cliche, clothes don't make the man, or the child. What they wear is merely superficial. When your twins are old enough to express their displeasure (or desire) regarding dressing similarly, then reconsider your stand on the duo's daily duds.