When we reached home, while I was preparing the rice, my mind was in a whirl. How should I handle this? In the end, I decided not to blow my top and to try to reason with him. I told him that I was very disappointed with what he has done and I wanted to know the reason. I kept repeating this statement a few times, and finally he seemed to get the message. He told me he didn't like the way the boy was fiddling with his hands and he also told me that the boy was "naughty in class". He also promised he won't do such things again (I hope he doesn't forget this promise).
Throughout dinner, I was rather quiet and Baby G ate his dinner without much fuss; it was quite a sombre moment. Normally, both of us would be talking non-stop but this time, I only spoke to him when necessary.
After dinner, I told him that he needed to apologise to his friend and I decided to get him to make a 'I am sorry' card and pass it to him on Monday.
I helped Baby G out with the card by writing the word 'SORRY' with dotted lines so that he could trace it out. As for the apple and the balloon, Baby G used a stencil to draw it out & colour it himself. After doing this, I asked if he knows why he's doing this and he told me "because I pushed yyyy.... (names will be withheld to protect minors)". I also asked him to repeat his promise.
Hopefully, Baby G will remember his promise... else at the next parent-teacher meeting, I'll be getting a lot of 'feedback' from the teachers.