Alan's 19-year-old son recently sat down exclusively with ET, opening up for the first time about the death of his beloved dad. Carter was playing hockey with his dad at the Pickwick Gardens ice skating rink in Burbank, California, on Dec. 13, when Alan collapsed at the rink. He later died at the hospital.
Carter says his father kept up his joking mood that day, even after the ambulance came to the rink to take him to the hospital. Carter confirms that Alan joked with the EMTs, gave him a thumbs-up sign and asked him to take a picture.
"He asked me to take a picture of him in the stretcher and, you know, he's telling all the EMTs to smile and put the thumbs-up, and he was cheery and happy and doing well, so I took the picture and then we were off to the emergency room after that," Carter recalls to ET's special correspondent Keltie Knight. "That was kind of a moment of relief for me. That's why, obviously, how that day ended was quite a shock."
Carter shares his father's touching last words, which was him being proud of his teenage son.
"The last thing he really said to me before going into the operating room ... he was joking because the first shift playing, he passed me the puck and I scored a goal, which he was ecstatic about," he recalls. "So, he's in the emergency room, kind of bragging about it, and of course bragging that he was the one who passed me the puck, and he was saying... 'Oh, got to play hockey with my son and got to watch him score a goal -- what a way to go out.' Before he went into the operating room, I got to give him a hug and say, 'I love you,' and then that was the last time I saw him."
Carter calls Alan "the perfect dad," and recalls how he would still send his father his essays in college to look over.
"He was my go to for everything, any advice I needed," he explains. "Especially with school, because he was way smarter than me. Everything I would send over to him. An open door policy is very, very true. Every time I ever needed anything, the door was open. He was constantly there to give. And so growing up ... he was, like, the perfect dad. Anything I ever needed, he was there for."
The Growing Pains star also imparted plenty of wonderful life lessons to his youngest son, including how to treat women.
"His main thing was always just respect," Carter says. "I think that was probably the biggest thing. He was a very respectful man. His main thing with me is what goes around, comes around. If you treat a girl the right way, you know, it's gonna come back to you. And so I think his biggest thing with me growing up was just be respectful with women -- be respectful to girls. And, you know, it'll work out in the end."
Alan also taught Carter how to get along and work well with others.
"Don't piss anyone off," Carter says about what Alan taught him about Hollywood. "That was his biggest lesson, because I can't think of anyone who he pissed off, or had a bad relationship with in this town -- which is very hard to do, as I've been learning, and as I've heard... I think his big thing was just to be nice to everyone, even if you hate the person, give 'em a fake smile and just be nice. 'Make it work' was one of the biggest things he would say for everything, whether it was me fighting with my mom or whatever, it was, 'Make it work,' always. And that was just something he did, and I think that's why he had the great relationships and friendships that he's had, and the respect he's had."
Alan's kindness will definitely never be forgotten to those close to him.
"I think just being the kind, generous man he was," Carter says about what he believes his father's legacy is. "He gave to so many people, and he never really thought of himself with anything. It was always about someone else. He wouldn't go do a gig somewhere if he couldn't squeeze out a ticket for me or for [his wife] Tanya, or for his sister or his brother, you know? He was always family first and people first. It was him last."
"It's his hard work and the way he gave back," he adds. "Whether it was with his diabetes foundation or with family, he was always giving back to people. And I think that's the most important thing for me, is his generosity and kindness was beautiful."
Alan's thoughtfulness could be seen in one of Carter's favorite memories of his dad.
"I think the most we [older brothers Robin and Brennan] have been reminiscing about is probably just Christmas -- my dad was the most amazing human being during Christmas," Carter recalls. "That was, like, just his time of year. He went above and beyond."
"One of my favorite memories was one Christmas when I was probably like 6 or 7," he continues. "When I was a little kid, I used to always sleep in his bed with him on Christmas Eve. And so one night, we're in bed, and on the roof above I'm hearing stuff, like, clattering on the roof and he freaks out. 'Oh, you hear that Carter? You hear that?' And I guess he had gotten someone to go onto the roof and pretend like it was hooves, and he runs out the door and pretends to be talking to Santa and all this, and I'm freaking out in the bed. So, it was just stuff like that. He went all out for family, and so I think probably the fondest memories that I've been re-running in my head have been about Christmas."
Carter admits he still has trouble dealing with the death of his father.
"I went home to Santa Barbara last week [where Alan lived] and that drive up, you think you're gonna come into the driveway, and come into the house, and he's gonna be there, and he's not," Carter heartbreakingly shares. "There's always that kind of that hope that, 'Oh, it's a crappy dream, it's gonna be fine,' but yeah ...I think that next day [after his death] was pretty rough for me. Definitely."
Carter later revealed what his last message to his father would be if he could give him one.
"Pass me the puck one more time, and I'll score tomorrow," he says.
Tune in to The Insider on Thursday for more of Carter's emotional interview, where he also opens up about Alan's star-studded memorial at his ranch in Carpinteria, California, which was organized by Robin.