The snap saw the two boys rock shoulder length hairstyles - a transformation that happened over lockdown. In the caption, the football pundit joked: "Locks-down [male facepalm emoji]."
Upon seeing the post, the youngest of the Lineker clan remarked: "He's done us here @harry_lineker, reckon he's jealous because he can't grow his." Harry then remarked: "He wishes he could."
WATCH: George Lineker downs glass of vinegar to show he's lost his sense of taste
Unimpressed, Gary hit back: "@anguslineker I've got more hairs than you have brain cells." To which, Angus replied: "@garylineker, easy I've got a university degree, do you?"
Fans were quick to wade in, with many suggesting that the brothers look like members of the nineties pop group Hanson. "Hanson haven't changed much since the 90's," said one follower, while another made reference to one of the band's songs, saying: "Mmm bop...!"
Gary is also a doting dad to sons George, 28, and Tobias, 24. The sports star and his ex-wife Michelle Cockayne were married in 1986 but split 20 years later with Michelle citing "unreasonable behaviour" at the time.
Gary Lineker shared this snap of his sons Harry and Angus
Following their split, Gary started dating model Danielle Bux after the pair were set up on a blind date in 2007. The couple tied the knot in a wedding exclusively covered by HELLO! in 2009 in Italy. However, in 2016, Gary and Danielle parted ways as they reportedly had different ideas about starting a family together.
Meanwhile, in April 2019, the former footballer reflected on the moment he was told eldest son George might only have hours to live after he was diagnosed with a rare form of leukaemia as a baby.
The football star is a doting dad to four sons
The Match of the Day presenter spoke about the heartbreaking time on BLANK podcast, saying: "I could cope with it while he was ill. I could cope with it while I felt there was hope. But there was a couple of times when they told us, they said, 'Honestly, we've got to warn you that we will be quite surprised if he makes it through the night.'"
Luckily, George pulled through, but that didn't stop Gary facing his worst fears during the dark period. "While it was always ups and downs and difficult times, there was always hope," he said. "We didn't lose him, so I don't feel we were dreadfully unfortunate, I think we were unbelievably fortunate because the odds of him making it were pretty low and he did."
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