Todays behavior is not the worst. It will get worse. Sometimes it will be days before the next attack, but it is coming. He is warning you as loud as he can, that he is aggressive and will attack your children. Why are you waiting for him to actually attack your children for the decision?
Roosters have ruined the whole chicken experience for a lot of people. I know he was the darling, "friendly and loving to be held," is how you see it. But they are not like puppies, in which if you love on them, they become life long friends.
Instead, when he approaches you for cuddles, what he is seeing is you are no threat, he has no respect for you. Chicken society is about pecking order. Every single chicken is either above or below, marches forth, or backs down from another bird in the society.
People often hope there is a way to train the aggressiveness out of a cockerel, but they do not start until the bird begins to show signs of aggression, it is IMO way too late at that point. There is not a lot of brain to work with, they are largely controlled by hormones. In my experience, once aggressive - they never loose that to the point that they can be trusted with all people. They are opportunist, which makes your children vulnerable. They tend to attack children first, then women and then men. BUT EACH ATTACK TENDS TO BECOME MORE VIOLENT. Inexperienced people vastly underestimate how violent an attack can be.
I am thinking perhaps wrongly, that these are your first chickens. At 16 weeks, not only can he be aggressive to people, but often times cockerels at this age can make the pullets lives miserable, especially if raised in a flock mate group without older hens to teach some manners. He is the biggest bird out there and becomes the bully.
I have read posts where people do keep an aggressive bird, and when going out to the coop/run they wear boots, padded jackets, gloves and heavy pants so they can take the attack without injury. That is not my cup of tea. I want to enjoy a peaceful flock.
This is not the bird he was last week. There really is no going back to that. One should not keep a cockerel chick unless they can dispatch them if they progress to this behavior. Why you think someone else would like a bird that bites and attacks does not make much sense.
Mrs K