I'm the parent of identical-twin boys. I've tried for them to develop their own identities and not be considered the same person.

• I've always dressed my twins differently and encouraged them to pursue different interests.
• As the boys grow older, they become less alike and appreciate being treated as brothers, not clones.

After a visit to the obstetrician at 12 weeks, we were told that there were two heartbeats instead of one. It was a surprise because there were no twins in the family, and we felt totally unprepared.

After finding out the news, I went to work and was speechless for the rest of the day. My coworkers kept asking me what was wrong, but I couldn't tell anyone yet.

Charlie and Thomas were born prematurely and, between them, weighed the same as an average-sized single baby. They were forced to spend the first week of their lives in a special-care nursery, and I could see their bond even then.

They wanted to be side by side at all times, and when hospital staff had to take Charlie away for some extra tests, he and Thomas were unsettled. Neither would sleep until the two were reunited. It was an anxious time leaving our tiny babies behind at the hospital, but we were glad they had each other for comfort.

In the hospital, it seemed that I was the only one who could tell them apart

To me, they had differences, which — though subtle — were noticeable. However, the two boys seemed identical to all our family and friends. People constantly asked if we would mix them up and if Charlie would become Thomas and vice versa.

At that time, I was determined that they would develop separate identities and not be considered the same person. I didn't want them to be known as "Copy" and "Paste."

Many of the early gifts we received for the boys were both of the same

While we were grateful to receive presents for the boys, we decided never to dress them the same. Charlie wore green, and Thomas wore blue — this helped people tell them apart. I pushed for brown to be the color for Charlie, thinking that Charlie Brown would make it even easier, but the fashion options were limited, and so it was green.

They are constantly referred to by the wrong names and have learned to respond to both

The boys have gotten used to being called either "Charlie-and-Thomas" or by the wrong name completely. One story that still makes me laugh is from their sixth birthday party. I was standing next to Charlie when the boys' 5-year-old cousin approached me and asked where Charlie was. I pointed next to me and said he was there. The cousin replied, "Not that Charlie, the other Charlie."

We treat Charlie and Thomas as brothers who happened to be born within six minutes of each other. When the boys started school, we asked that they be put into different classes.

There was another set of twins in their school, and they had requested to stay in the same class, but we felt it would allow Charlie and Thomas to be individuals, develop their own friends, and make it easier for their teachers.

It was the first time they spent long periods away from each other, and we were worried about how they would feel, but they thrived being able to act as individuals.

As they grow older, they become more different

They now opt for different hairstyles; one will have long hair while the other goes for a shorter cut. Their interests are also diversifying; Thomas has become obsessed with basketball, a sport that Charlie has little interest in.

Perhaps the most significant difference is the professions they want to enter.

Thomas wants to work in IT or engineering, so his high-school subjects consist of math and science, while Charlie aims to become a lawyer, and focuses on law, business, and finance subjects at school.

I think their diverging personalities and interests comes down to the decision we made to dress them differently as babies.