Can I take my son on a boat trip?

Sure! If he is a surfer he will love it! It’s an unforgettable experience for him. If he is a young kid, say under 12, maybe he won’t be paddling out on every occasions (for example on a bigger day) but he will surf more and better waves than ever before in is life.
We’ve had 9 years olds, 11 years olds, 14 years old girls… They all had the best waves of their lives! There might be a problem though… they will never stop asking you to come back to Sumatra!