AC Milan did not know it at the time but when they signed Antonio Donnarumma in 2006, they effectively acquired two goalkeepers for the price of one.
"When I left home, Gianluigi was so small," Antonio recounts in an exclusive interview with Goal.
"He used to watch me play, watching all of the Milan games and he became a Milan fan from a young age because of this.
"I used to bring him back my shorts and jerseys, so maybe he was destined for Milan from when he was little."
Indeed, the young Gigio only ever wanted to emulate his big brother, one that he rarely got to see as Antonio attempted to make a career for himself in Milan, far from the family home in Castellammare di Stabia, just outside Naples.
In the end, Serie A success didn't happen for Antonio, who spent most of his time with the Rossoneri out on loan before another ill-fated spell at Genoa ended with him moving to Greece last year to link up with Asteras Tripolis.
He is still only 26, though, and could yet return to Italy, where his little brother is not so little anymore.
Indeed, the 1.96m (6ft 5in) tall Gigio has already become a San Siro superstar at just 18 and Antonio is not in the least bit surprised, given Goal's NxGn winner showed an aptitude for their common role from a very young age.
"He watched me on the pitch, and in training, and I think that, because of that, he wanted to be goalkeeper right from the start," Antonio muses.
"From the age of five, he was putting on his gloves to go in goal.
"We've always been far away from one another, because I left at 14 and we saw each other little, also because he had school.
"We met only at public holidays, like Christmas and Easter. But we hear from each other every day. We talk about my experience here in Greece.
"We play Playstation together online. We do video chats every day to see one another and be together.
"But we speak little about football."
They prefer it that way. But then, Antonio freely admits that there is no longer much need for him to advise Gigio, who seems to embody the idea of having an old head on young shoulders.
"It was only normal that until recently, when he was not so big and was still really small, my parents and I gave him advice," Antonio explains.
"That was important because, at his age, finding himself in such an environment, in something maybe much bigger than he, he needed some guidance.
"However, he really handled the situation very well thanks to his personality and character, always demonstrating his value and ignoring the criticism.
"The characteristic that always strikes me most is his personality. It's something out of the ordinary.
"He manages to stay calm in goal, as if he were a goalkeeper of 36 or 37 years of age. He really plays the game with so much tranquillity.
"I don't think that he will ever stop improving. He can be as big a phenomenon as he wants but he needs to always improve in every aspect, and to train well day after day."
Staunton on Donnarumma
Peter M Staunton has some valuable advice for our #NxGn winner, AC Milan goalkeeper Gigio Donnarumma. Do you agree? Posted by Goal.com on miércoles, 22 de marzo de 2017
Given his youth, temperament and talent, Gigio has already been the subject of much transfer speculation, with Manchester United, Real Madrid and Chelsea all said to be interested in a player who has not yet committed his future to Milan beyond 2018.
However, when asked about his brother's contractual situation, Antonio simply says, "For now, he's serene and calm."
Just as he is, and always has been, on the pitch.