Transcript for Father at center of international custody battle speaks out
years ago. But they never returned. Brann, now able to see his little boy only when he travels to Brazil. The visits that I have are at the discretion of my ex-wife. She decides when I get to see him. How often. They're afterschool. In the presence of armed guards who watch and report everything I do. Reporter: This morning, the FBI says they have evidence that Marcelli, along with her parents, conspired to kidnap Nico. Days ago, federal agents arresting Nico's grandparents in Miami when they attempted to ternt country. According to this affidavit, Nico was enrolled in a Brazil Yant school run by his grandmother three months before he left Houston with his mom. When they arrived, Marcelle had already accepted a job there. His grandfather bought him a plane fikt on back to Texas to make it seem like he was coming home. This morning, an attorney says it's absurd for the united States to arrest her client's parents. Adding international law gives Brazil the right to decide where the child lives. For "Good morning America," kayna Whitworth, ABC news rg los Angeles. Thank you so much, kayna. And Nico's father, Chris Brann joins us now. How has it been for you over the last five years? You know, it's -- it's about the hardest thing you can imagine because there's never any closure. If there were a death in the family or some other pivotal event. You can book end it and move on and grow from it. This is an opportunity where every chance you get, there's more injury. More harm. More pain. And, it's a very isolated and lonely road because you know, you fight and you fight and you fight behind the scenes. Nobody knows what you're going through. You have to show your public face to the world. You have to go to work. You still have to, the in my case, see patients and try to be positive and juf lifting when deep down inside, I'm suffering every day. My home is a mausoleum to my son. Everything in here remind mes of him. But I staid in the house, in hopes that when he returns, he'll have something that he will remember that will trigger that emotional response of what it was like when he was here. And you petitioned the FBI to take this case against the grandparents some time ago. It seems like a very extreme step. Is it fair to include them in the fight? Well, absolutely. There's though doubt that they should be included in this. You have to understand. I did not take this decision lightly. It's not something that I wanted to do. I really felt like I didn't have any other options pip had exhausted all of the other things I felt like I could do in order the get Nico home. I've been to Brazil over 20 times pip have met with the foreign judiciary. I fought it in the state and federal court. I met with the ambassador in Brazil sprip been to capitol hill. I have petitioned our senators and congressmen. I have testified in congress. I have done everything I know how to do. Honest lirks the thing I have done the most is begged this family for the opportunity to be in my son's life. And nothing has yielded any dividends. Soy really felt like this was the last tool in the arsenal that I had to play. It's not something I wanted to do. I didn't feel like I had any other options. And with that said, do you think what this latest step, that there's a chance you could drive a bagger wedge between you and your son? You know, absolutely. There's the potential. No doubt that in these parental abductions, the classic story is the alienation part. The abducting parent will use the child against the left-behind parent because alienation is central to this theme of trying to remove a parnd from the life of a child. And I certainly have that fear. But hontsly, I have had that fear the whole time. Why I have fought so hard to be a constant presence in my son's life over the last five years, despite the challenges. You said you have been to Brazil over 20 times. Each time, do you have a chance to see him? No, absolutely not. I've been down there multiple times when I have not had the opportunity to see him. In fact, every time I do go, there's the element of fear that I won't be able to see him. The times I do get to see him have been amazing. There's the void that only he can fill in my life. But -- I have been able to see him -- recently, which is fortunate. I saw him two weeks ago. Right before the grandparents made a trip down here to the United States and all of this started. If you're able to get Nico back to the United States, do you have any worry about him reacclimating to the states? Yeah, absolutely, I do. I have reached out to other people who have been in my situation who have had their children returned. They have let me know some of the things they have done. Some of the missteps they have done, actually. The reacclimation process. I would love to dream about a possibility of trying to reacclimate him. Right now, I don't have my some back. That is my top priority. This is an opportunity for me and the thousands of parents going through what I'm going through. We have sought this type of media attention for all of us for so long. And truly you're giving a voice not only to me but for the thousands of left behind parent who is are fighting this fight. Who have never had the opportunity to tell their story publicly. And hopefully, this will shed a light on this issue at large. And I really appreciate the opportunity. Thank you so much. A big thank you for Chris Brann for that. At the end of the day, there's a child in the middle of all of this. And you don't know how many, as he said, how many families go through this. And he's done so much over these years. Hopefully, he can resolve it.
This transcript has been automatically generated and may not be 100% accurate.