"That's my older brother. When people see me, they see Nick," he says. "Everything that he's taught me, I'm going to live through. I'm going to make sure I take it and I use it. And I'm going to make sure everything that he wanted me to do, I'm going to do it."
"I spoke to him six hours before he passed," he tells ET. "He was in a normal state of mind. Nick was fine, he was cool, like anybody else would be on New Year's, honestly."
"He called me on the phone and I was working. I was busy, so I told him I would call when I got off," he adds. "It wasn't really like he was messed up or anything like that. He was normal."
Walker Jr. says that, hours later, however, he then heard from his father, who told him to come to the Intensive Care Unit at Altamonte Springs Hospital, where Gordon was rushed to after he was found unconscious.
"I tried my hardest to wake my brother up. Me, my father and [Nick's girlfriend] Laura [Leal] were there with him," he recalls. "We were trying as hard as we possibly could to wake Nick up but, you know, it's just how it is. God's plan."
"Nick wasn't speaking at all. He wasn't speaking, but he could hear me," he adds.
Walker Jr. tells ET that "of course" Brown's death affected his brother.
"Of course it did. My brother loved her," he shares. "Everything. All this. Everything that he's been going through has taken a toll on my brother."
"Everything. Everything that the media's been throwing at him, everything that life's been throwing at him, yeah, it took a toll on him," he continues. "He lost somebody he really loved. It's hard to be the same person when you lose somebody."
Despite what's being written and said about Gordon in the press and on social media, Walker Jr. hopes people will look past "judgment" and see his brother the same way he did: as "a great person."
"Nick was doing so good," he says when asked if Gordon was recently struggling with drug addiction. "Nick was not how people are portraying him to be at all. Nick is not like that. People got everything all twisted. Everything's so twisted, with the media and how they perceive my brother."
"Nick was a great person, and he was loved by many people," he adds. "Everybody's entitled to their own opinion, but Nick was a great person. Nick loved everybody and people fail to realize that. All they do is read tabloids and make a judgment out of somebody off of that and that's not the case of my brother. I've known the man for all of 27 years, so I think I have a better judgment on the type of person he is than the majority of the people who are writing and saying [negative] stuff about him."
As ET previously reported, the District 5 Medical Examiner's Office shared that Gordon's autopsy was conducted on Thursday morning, though results will not be in for two to three weeks pending further investigation and testing. Gordon's attorney, Joe S. Habachy, referenced his client's alleged battle with drug addiction in his own statement given to ET.
"My heart is heavy today after learning that my longtime client, Nick Gordon, died at the young age of 30. While I cannot speak to the specific circumstances of his death, I can say that it's been truly heartbreaking to have witnessed firsthand the total devastation that drug addiction has wreaked upon a group of young friends, all of whom were loved and had immense potential," his statement read. "Despite all of the incredible challenges Nick faced over the last few years, I can honestly say that he worked hard to hold his head up and stay sober and that he genuinely wanted a happy, healthy life with his family more than anything else. My heart goes out to the family and friends Nick leaves behind and to any other families dealing with the losses and heartache caused by drugs."