弟弟 In School

It has been 2 weeks 弟弟 start his nursery. So far so good except still don't want to wear uniform to school. There was one day teacher helped him to change to uniform in school. Teacher told mommy, there was a deal behind that. Now 弟弟 like 'glue' to his class teacher, therefore his teacher told 弟弟 if he wants teacher, he has to change to uniform. That's the only day he came back home with uniform.
Now, mommy bring him to school, spend 10-15min sitting together with him at the waiting area as 弟弟 request. He only let mommy go when teacher called him to join the group for singing (class going to start as well).
Don't know how long needed to train him go inside the school without mommy, just like me last time. But at least now弟弟 goes to school without cry, this is already a good progress to him.