Of Barry, enough is known and is still being written. But Derek, the original "continental playmaker" of Ibrox? Now this is definitely worth a catch-up.
These days Derek Ferguson is 46, doing some media work, and going in to schools to represent Show Racism The Red Card. The mere sight of him, as I discovered again yesterday, reminds you of that slightly hunched, clever, cultured midfielder who blazed on to the scene at Rangers in 1984. By the time he was 18, Derek Ferguson was truly the next Graeme Souness.
It is ironic, then, that two men more than any others would influence Ferguson's career, for good and ill: his father, Archie, and Souness himself. In some ways it is an uncomfortable story.
Archie Ferguson, a roof-sheeter who is now 67, did something quite remarkable in his life: in Derek and Barry Ferguson he reared and taught two of Scotland's finest midfielders of the past 30 years. Barry, through fate, got most of the limelight, but Derek was still pretty special. Indeed, but for injuries, some older Rangers fans today still believe that Derek was the better of the two.
When he first appeared, Derek was thoroughly intriguing. From somewhere his instincts were those of a European: he was composed, he didn't rush; he calmly stitched Rangers' play together. 'Cultured' was the very word for him. It was actually a little baffling to see a wee Scottish lad play like this.
"My dad was my biggest influence - and I guess for Barry, too," says Derek. "I remember as a wee kid watching my Dad play football. He had fantastic skill. He made everything look so easy.
"My dad made me the player I was. He always said things like: 'Never panic on the ball. Always take the ball. Be brave on the ball. Keep your head up and use the ball.' I had these phrases in my mind from when I was a little kid. It all stayed with me."
Endless summers on the beach with his father, playing keepy-uppy and not much else, produced the Derek Ferguson that many swooned over. With the Graeme Souness revolution just starting at Rangers, it should have been the perfect scenario. Instead, it all went sour.
"Graeme Souness used to get annoyed with me. He thought I was taking far too many touches on the ball. He actually thought I was too greedy. The bit that was true was that I knew I had ability, I knew that I could dominate certain situations.
"Maybe sometimes I wanted to show my opponent that I could dominate him - with a wee flick or a wee trick. I think Graeme admired me as a player, but also believed - and this was absolutely not true - I was out on the town every night, that I was a bad boy. I can assure you that wasn't true.
"The problem was, Graeme wanted me to live his lifestyle, or the lifestyle of more experienced players. But I was still young. I was 19, 20, 21. Graeme liked to haul me up in front of the press and give me a caning. He had a pretty odd attitude, to be honest."
Between 1984 and 1990 Derek played over 120 games for Rangers, and at first, along with Ian Durrant, was integral to the Souness strategy. His talent shone out. But then Souness, for whatever reason, began to turn against Ferguson. "What held me back at Rangers was my shoulder dislocations - in both shoulders," he says. "It kept me out for long periods of time. On one occasion Graeme took it upon himself to try to put one of them back in himself on the training pitch.
"He put his foot on me, he was pushing it, twisting it, turning it. I was in agony. I was screaming at him: 'Get aff me ya f****** idiot!' The next day the surgeon looked at the mess of it and said to me: 'What happened here? You could have been damaged for life with this.'
"I used to love training games against Graeme. I knew I had the ability, and he knew it, too. Off the pitch I was always very respectful towards senior pros like Graeme, Terry Butcher, Ray Wilkins and others - I went out of my way to be respectful towards them. But not on the training field. On the training pitch I felt very comfortable in that company. I'm not being big-headed but I looked at some of these guys and I thought, 'I'm as good as them, I can hold my own here.'
"There was definitely something about Graeme's attitude which was strange. Look at Ally [McCoist] . . . he was jealous of him. Everyone loved Ally, and Graeme knew it. He didn't like it. He resented it.
"I don't think Graeme liked young upstarts coming along who maybe had a lot of skill, and threatened him in the football sense. Sometimes he'd take things into his own hands.
"It used to amaze me that Graeme had played at the level that he had, and in the company that he had, yet he still felt this wee insecurity within him. When I got older - at Hearts, at Sunderland, at Falkirk - I loved it when fine young players came along who could nut-meg me. I'd embrace them. I never felt annoyed by it. I just didn't get Souness' attitude."
By 1990, says Ferguson, there was enough strain between him and Souness to spell the end of his time at Rangers. He was still only 24 and, doubtless with faults on both sides, was on his way out the door.
"Graeme told me I was being sold," says Derek. "He said he'd spoken to the Hearts chairman, Wallace Mercer. I said to him, 'naw, I'm not going anywhere. I like it here at Rangers. I've got 18 months left on my contract.' Graeme said, 'you're going, I'm selling you.' I said, 'naw, I want to stay.'
"Eventually I spoke to my dad and I decided to leave. Graeme had told me that, not only would I not be playing for the Rangers first team, but that he'd make sure I'd sit on the bench for away games at reserve and even youth level. I said to him, 'gaffer, if that's your mentality, you just carry on, you do that.' I hated that sort of threat. My dad said to me: 'Son, what do you want to do on a Saturday afternoon? You want to be playing football, right? I think you should go to Hearts.'
"The funny thing is, after all of that, I still really liked Graeme Souness. And I still like him. I loved Souness the player. But what a guy he was."
Amid all the football that followed - and the injuries - at a host of clubs, just two Scotland caps were won. It is quite a blasphemy, that.
"I loved playing football, I loved the dressing-room. I earned well, but it didn't make me wealthy, which never bothered me. Money has never been a priority for me, just my family and my happiness. It was quite an adventure, my career."