They've had him at the Sunderland Academy rather than at Newcastle's since he was 8 so I think that goes someway to answering your last question. They've clearly got their lad's best interests at heart over and beyond their own allegiances.
I'm not sure why so many people (not you) are insistent on casting aspersions over his family when all precedent shows that they're clearly not the SAFC hating, staunch Mags that people suggest.
Absolutely, 100% this. We are going to end up driving him away if fans continue to talk nonsense about him and his family.
They may be big Newcastle fans. But if they were such big Newcastle fans that they didnt want him playing for Sunderland, he wouldn't be playing for Sunderland
