Below is a sampling of reactions and insights in the wake of the tragedy.
"He was the standard. You wanted to recruit more guys like Jovan Belcher. I still have photos of him holding our baby, who is a first-grader now. Our family loved him. He was the standard of what you wanted to have in your football program."
"He was never on any lists. He was never a guy in trouble on campus. You got on lists for different things in football, like missing study hall, or if you don't go to class or get in trouble off campus. He wasn't one of those guys. He was what we expected our players to do and be."
"He was a special player. He was one of those handful of kids when you're putting your game plan together and drawing it up, you say, 'How are we going to block No. 9?' Just his relentlessness. That was the thing you remember about him. He was just relentless. Every time you saw film from another game, you said, 'God, this kid plays so hard with such passion.' He's one of those handful of players you remember forever."
"He was not a kid that you would say, he's 6-3, 245. This kid earned his reputation on how hard he played. Anyone who has ever played respects those guys more than anyone else."
"It's hard because me and Jovan -- when he first got to Kansas City I had just got there; I had been there for two years. He was a free agent guy that just came in and grind(ed). I saw him grind. I saw him get knocked down, I saw him get back up. It was hard, because for four years I spent a lot of time with him on Thursday nights during the week and stuff like that. It was a hard one because I knew both of them. He met [Perkins] at my house. It was hard because he was a strong teammate of mine. I had much respect for him, a lot of love for him. I just can't believe the situation that happened."
"I've been together with [Belcher] and Kasandra multiple times. They seemed happy. I mean, they had their issues at times, but who doesn't?"
"The one thing about Jovan, when he's in love, he's in love. I think females bring out the passion in him. He was a lover. He would fall in love and be with that girl. In college he had one girlfriend. After his sophomore year he was with her the whole entire time. And he loved her. He's very passionate. I wouldn't say he's wild. He was a passionate lover. Us guys in college, you're there for a couple years and have your fun and leave. Jovan is a different case. He fell in love with a girl. I saw this and I couldn't believe it, for him to do something like that."
"He wasn't a crazy one. He wasn't someone we couldn't talk to or hang with or play a joke on. He was one of our brothers. He was one of those guys. You could call him and talk to him."
"No one really feels like this is Jovan. No one would ever think that he would even be capable of something like that. I never saw Jovan get out of control. I never witnessed Jovan getting out of control. Never heard of any incident of anyone lashing out. That was never him."
"He did his partying. [But] he was more of a guy who was always around his teammates. If we were all partying, he was there. He was more of a guy who helped out and made sure people were focused. We have a couple guys in the NFL, I'm not going to name names, who were a little out of hand. He was there to help calm them down."
"He was a quiet dude. I'm going to be honest. Coming into it, he wasn't one of those flashy dudes. He was quiet and motivated and believed that he was going to go to the NFL. He knew. He had a feeling. 'I'm going to work my ass off and get there.' "
"He always had a smile on his face. Never one of those dudes that lost his temper. Never lost his temper in a meeting. Only time he ever took out anything was always on the field. It was never a point where he would lose his mind or get in a fight with anyone."
"I remember Jovan from his recruiting trip. I was with the guys that hosted him on his recruiting trip. I remember him coming out of high school. I couldn't be more saddened and more disappointed. It's so tough for both families. It just shows you how fast things can happen. Looking at the situation, I wish I had stayed in better touch with him. When you leave college you start going your separate ways. I wish I had stayed in contact with him, because you'll always wonder, could you have helped? Could you have been there for somebody? With this situation, I've been praying for both families constantly. I just pray that something like that doesn't happen again."
"He didn't have violent tendencies. I do remember the type of person that Jovan was, and to see what happened is so shocking. That's not the kind of person that he was."
"To do either one of those acts [of a murder-suicide], something had to snap. You can't be in your right mind. Especially with Jovan, someone who is not like that. You can see hot-headed people maybe doing something like that, but that wasn't Jovan. I'm totally shocked."
"I honestly felt like they really loved each other and their baby. It seemed like they were the perfect couple. I never saw anything wrong."
"I've tried to pick my brain and think of like if there was any reason. I really want to know what the reason was that made him do what he did. I'm so shocked. I would have never ever thought anything like this would happen to them."
"[Perkins] was the sweetest person I knew. Very generous. Kind. Everyone she met fell in love with her. She was amazing. A really good friend."
"[Belcher] wouldn't have had a reason to be jealous. She was here when she could be. She always had dinner ready for him. Did laundry. Baby was always cleaned and pampered."
"I didn't know Jovan as well as I knew Kasandra, so if there was a side to him that was not what I saw, then maybe I didn't know him as well as I thought. Definitely when you get in front of people you act a different way. So I'm sure that's what I got most of the time. I probably didn't get to know the inner Jovan."
"They were really good together I thought. They always appeared to be very happy. They appeared to be in the kind of relationship that most people who weren't in a relationship would envy because they seemed happy all the time."
"She just wished that every now and then instead of him staying out late he would just come home."