In July 2010, Morrison made his Major League debut at age 22. The Marlins promoted the outfielder when his father, Tom, was stricken with lung cancer.
Tom Morrison provided every opportunity for his son to achieve his big league dream. Five months after Logan reached baseball's highest level, he lost his father to the cruel disease.
"Logan has really come through a lot," said Diane, Logan's mother. "Nobody should really have to do the things that he had to do. The one person in his life who worked so hard to get him to where he's at is not here to share it. I'm sure it's very difficult for him."
Now 24, Logan Morrison is an established part of the Miami Marlins. He's the everyday left fielder and regarded as having the upside to become an All-Star-caliber player.
To honor his father, Morrison is active in raising awareness for lung cancer. He has an annual "LoMo Camp for a Cure" in January at the Roger Dean Stadium complex in Jupiter, Fla.
And when Morrison hits a home run, he recognizes his dad, who was in the Coast Guard, by making a military salute at home plate.
"I hope he never stops doing that one," Diane said of the tribute.
Through all the ups and downs Morrison has gone through on and off the field, a constant for Morrison is his mother.
"She's always been there for me as either a shoulder to cry on or to vent to," Logan said. "Whether it was going through the stuff with my dad, I tried not to show emotion. That doesn't always happen. I tried to be there for her."
Diane, who makes Slidell, La., home, is always a phone call or text message away from offering support to her son.
"I'm here just to be that voice, I guess, who says, 'Everything is going to be OK,'" Diane said.
Along with being a rising big league talent, Morrison also is one of the game's emerging characters. Easygoing and personable, he's a media and fan favorite. He's no stranger to the spotlight or a bit of controversy. He's one of MLB's most visible faces on Twitter.
"Every time I see him on TV, it's exciting. 'That's my son!'" Diane said.
Pausing, she laughs and adds: "And every time he does something on Twitter, it's, 'Oh my God, that's my son!'"
But at the end of the day, Diane is a proud mom who is tickled that her son is making a living playing baseball.
"I have no great words of wisdom, but every time I see him, I just think that he's done a great job," she said. "He's had to do things for himself lately. But he's overcome it. The adversities were there, and he's done a great job at making things work. I'm not so sure I would have done it as well as he has.
"I couldn't do it without him, honestly. With Logan, it makes life a little easier to deal with."
To offer her son guidance, Diane sometimes has to wear many hats. There are times she finds herself repeating advice once offered by Logan's father.
"I try to remember some of the words that Tom used," Diane said. "I try to put those into practice for Logan today. I hope they help. I hope they don't sound corny. But they make so much sense."
At home, she follows her son on television, with the MLB package. If she detects a glitch in her son's swing, she might say to the screen: "Keep your head down on the ball."
Or if Logan reaches at a pitch, Diane might yell: "Wait for the ball to get deep!"
Or she may just go back to the basics: "You've got to hit it to the gaps. Line drives."
"I'm a couch coach," Diane said. "Of course, it doesn't do much good sitting at home."
Diane and some family members were at Marlins Park for the season opener. And she will get to as many games in Miami as she can. Usually, it is when others in the family also can attend. Otherwise, she catches the games on TV.
"She watches every night," Logan said. "She tries to give me words of encouragement when I struggle. Kind of like my dad did. She tries, but it's not the same. She'd ask me what pitch I swung at. She will try to give me feedback."
When Tom Morrison passed, Logan and Diane were at his side.
"We were in the room. He was sleeping," Logan said. "I said, 'I don't want him to go yet.' She's like, 'I don't want him too either. But it will be OK.' In the time of her need, she was there for me. That's something that sticks out to me."