Longstaff announced himself to the Premier League in style on Sunday, scoring the winning goal for Newcastle against Manchester United on his league debut.
The teenager's older brother, Sean, played alongside him at St James' Park. But that's not the only family tie Matty has to Newcastle, for whom the pair's uncle, Alan Thompson (Guardian), also played.
Thompson, though, is perhaps best known for a seven-year spell at Celtic, where he earned his one and only England cap.
And that could explain why Matty can be seen in Celtic colours below...
Great picture of the Longstaff brothers, I particularly like Matty's threads...— Stan Collymore (@StanCollymore) October 7, 2019
Thompson came through the ranks at Newcastle but made his name at Bolton Wanderers, before spells at Aston Villa, Celtic, Leeds United and Hartlepool United.
The 45-year-old was capped once by England in 2004, while Sven-Goran Eriksson was manager.
Collymore, who played alongside Thomspon at Villa, is known to have a soft spot for Celtic.
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