His granddad is a Tigers supporter, even though he now lives in Northumberland.
And the Germany star's English dad, Chris, supports Everton so rows brew when they clash.
Holtby, nicknamed 'Fritz' by his dad, a former soldier who was based in Germany, said: "There's also a rift when England play Germany. My dad is a serious supporter.
"My granddad Harry is a Tigers fan. Unfortunately, he lives in Northumberland and it's a long way to come down to a football match.
"Hopefully I'll see him in Hull when we play up there. I've a lot of family there - the Holtby family is everywhere!"
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