It took me years to figure out that my son had difficulty changing his activity at the drop of a hat, and that any major change like moving, starting school etc. caused him great anxiety. By the time he started Kindergarten, I was able to tell the teacher that he didn't like the lesson changes every 15 minutes but it wasn't until he was about 8 years old that I began to get the sense that the small daily transitions that he had to cope with were provoking extreme anxiety for him.
Some signs that your child is having difficulty with transitions, from birth to teenagehood, would be:
1. Fussiness as a baby when someone else gives a bottle, changes a diaper, going to sleep, waking up, unexpected noises, unexpected visitors and unexpected behaviour from the people around them.
2. Refusal to try new food or leave the house. Distress when siblings stop playing with them. Difficulty shopping (this one is easy to spot - if you take your child shopping and buy him/her a chocolate bar the first time, every time you go after that, your child will expect the exact same experience).
3. Refusal to move from crib to a bed, coming to the table for dinner, changing clothing, rearranging furniture, having to share a bedroom. Although the criteria for Asperger Syndrome includes the fact that the child should not have difficulty with self help skills, I have found that this is an extremely difficult area for my son. It took me two years to get him to brush his own teeth, only because he preferred to continue on the way we were. After all mothers are here to look after their kids, right?
4. Difficulty when getting a new pet, extreme distress on the death of a pet (our cat got killed when my son was 4 and he cried for 6 years (not continually) whenever her name was mentioned), anger at the unexpected behaviours of a pet.
5. Anxiety when moving to a new house, moving to a new school, making a new friend, going away on vacation, becoming interested in girls, having a new teacher.