You had success - he tried it!
He might need time and he might need to explore his feelings- fear, frustration, ect. (maybe skip the lectures- see below)
Frustration is normal and healthy.
"We justify our manipulations of people, events, and rules on our children's behalf in the false belief that when we eliminate their frustrations, we're demonstrating our love. But the truth is, when we prevent children from experiencing frustration, we're keeping them from developing the vital life skill of learning to adapt, which is an ability they'll need throughout their adult lives.
Rather than coldly admonishing children to "deal with it" when they're upset, adults need to help frustrated children along to what psychologist Gordon Neufeld calls the Wall of Futility. Children need to feel their real feelings of sadness and find their tears. And when children, often with your help, can come to their tears about whatever they want and can't have, or whatever is broken and can't be fixed, they become able to move on — to adapt."
When we are there to help them through the tears with our "soft" voice and acknowledge their feelings we are " helping them find find expression and release.
Let it be OK not to be perfect by our own example. Be proud of their successes - no matter how small. With this small success and adaptation he will have "discovered that while life may not always unfold to "his" liking, "he" can adapt to it and find "his" way back to joy.
When we intervene because children are frustrated — believing we're doing so out of love and care — we prevent them from learning the lesson of adaptation. As a result, when they experience something upsetting later in life, either they will demand that circumstances bend to their will or they will become aggressive. They will become adults who cannot cope when things don't conform to their liking — like people who demand recompense when they're disappointed or who numb themselves with substances or distractions just so they can handle life's more difficult moments.
Think about difficult times in your own life. One of the greatest gifts we can give children is the ability to find their tears when they're frustrated. Tears actually release stress hormones and toxins — as usual, Mother Nature knows what she's doing.
What happens when children don't feel their sadness or find their tears, and we don't bend the world to their liking? Unresolved frustration produces aggression. Verbally or physically, children who are prevented from getting what they want and who lack the ability to adapt will become aggressive. And when we "up the ante" and punish children by taking more and more things away, we simply move them toward either increasing their aggressive behavior or hardening their hearts.
How to Approach Frustrated Children
When children are frustrated, it's not a good time to teach, advise, or lecture. Children cannot process what you're saying when they're upset, and the onslaught of words you deliver to try to convince them to see things a different way just aggravates them more. Think of it this way: Language is a function of the left brain, but feelings originate in the right. When children are stuck in the storm of emotions whirling around in their right brains, they don't have access to their verbal, logical left brains, which might be able to make sense of or benefit from your well-meaning suggestions. In a sense, your efforts to cool kids down by offering rational suggestions is like knocking on a door when nobody's home.
We should all embrace the idea that there's value in helping the children in our lives chalk up another adaptation, knowing that each time they do, they're adding to an internal reservoir of confidence and resourcefulness that will help them navigate life's ups and downs.
Parents and grandparents often miss the forest for the trees, wanting kids to be — or at least appear to be — happy in the moment, without considering the cost. When children grow up believing that they can really be happy only if events in their lives unfold in the particular way they want them to, they become adults unable to cope with experiences outside their control, and they suffer as a result. Parents and grandparents who help kids learn the essential life skill of adaptation give them a priceless gift — the means to be happy regardless of whether people, events, or circumstances conform to their expectations.
When we raise kids by modeling our own adaptation and help them "hit the wall" when they're stuck, we equip them with the ability to surf life's ups and downs with their eye on the prize of enjoying every moment of their precious lives." excerpts from an article How To Deal With Frustrated Children by Susan Stiffelman
Hope this helps (wish my aggressive brother-in-law had learned this sooner)