I don't think you should give him isolated chlorophyll, give him green juices instead. I hope you have a juicer, the green juices have the chlorophyll in tact with magnesium and everything naturally in it.
I've been drinking 16.9 ounces of green juice x's 3 daily
Made out of cucumber, celery, parsley, kale and romaine, no fruits, no sweet veggies like carrots and beets, just greens.
That should help him. Adjust the dosage for his age.
I don't think people should take chlorophyll separately. Take the whole food. The green juices will give you plenty of chlorophyll.
I am even going to just chew these leaves so I can get the fiber in me too. That should have it's own benefit.
No more pancreatic pain either and flawless skin, that's what I've noticed. Just thought I'd share.