T.T.
Hi I., I work in open heart surgery and if all that he's having done is a VSD, it's a quick surgery and he should bounce back quickly too. Surgery is always scary for parents, but be assured that he will be very well taken care of. It will also be scary to see him once he comes out (lots of tubes and probably still on a ventilator) but he will be made comfortable. The breast bone heals quickly and he should not feel a lot of pain. The best thing you can do is comfort him. Be by his side and hold his hand. Best wishes to him for a speedy recovery.