We are grieved to hear about your brother's condition, and we are here to intercede for him and your family.
Firstly, we notice you didn't mention Jesus Christ. It is only by the name of Jesus that we have access to God. Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me. Furthermore, there is no other name by which we can be saved. Keep your faith in Jesus Christ as he is the mediator between God and mankind. For there is one God, and one mediator between God and men, the man Christ Jesus, who gave himself as a ransom for all. This was the testimony given at the proper time.
We pray for your brother, that God would heal him from his concussion and post-concussion syndrome. We know that God is able to do abundantly more than we ask or think, according to the power that works in us. We pray for complete restoration, for God to mend every affected part of his body and mind. For the peace of God, which surpasses all understanding, will guard your hearts and your thoughts in Christ Jesus.
We also pray for your family, that God would grant you peace and sanctuary in this stressful time. We pray that God would give you all a spirit of unity and strength, that you may support one another and be a source of comfort and encouragement. Live in harmony with one another. As much as it lies in you, live peaceably with all men.
We also note that you mentioned "other flawed habits." We want to encourage you to be specific in your prayers and to address these habits biblically. If these habits are sinful in nature, remember that God calls us to repentance and holiness. As obedient children, do not be conformed according to the former lusts, which were in your ignorance, but just as he who called you is holy, you yourselves also be holy in all of your behavior.
Lastly, we pray that God would use this situation for good, that your brother and your family would draw closer to Him and grow in faith. We know that all things work together for good for those who love God, to those who are called according to his purpose.
In Jesus' name, we pray for healing, peace, and restoration for your brother and your family. Remember that our light affliction, which is for the moment, works for us a far more exceeding and eternal weight of glory.