The England and Real Madrid superstar was watching younger brother Jobe, who plays for the Black Cats, during their 2-2 draw against Blackburn.
Some of the Sunderland fans in attendance at Ewood Park were heard dropping their infamous X-rated chant about Newcastle icon Shearer, who spent four years as a player at Ewood Park.
As the 'Shearer is a w*****' chant was sung, cameras pointed at Jude appearing to jokingly mouth the same words with a grin on his face.
It should be stressed that the 21-year-old wasn't uttering the words with anywhere near the same amount of gusto as the Black Cats faithful.
Attending the match with parents Mark and Denise, Jude has made it an annual tradition to watch Jobe in action on Boxing Day with Spanish football on hiatus.
He wore a Sunderland scarf as he watched his brother beat Hull - but this year, he wasn't fortunate enough to witness another win as the Wearside outfit battled to a 2-2 draw at promotion rivals Blackburn.
The home side led at half time through Yuki Ohashi's 13th-minute goal, however, Sunderland turned the game around with goals by Chris Rigg and Wilson Isidor inside five second-half minutes.
But a 90th-minute goal by Harry Leonard ensured the spoils would be shared.
The older Bellingham brother was able to go to the game with the Spanish football season on pause for the winter break.
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Jude enjoyed a stellar first season at Real Madrid having won a LaLiga and Champions League double, as well as the Supercopa de Espana.
He's already added Super Cup and FIFA Intercontinental Cup winners' medals to his name this term, although Real Madrid haven't had it all their own way this season.
They're currently second in LaLiga, a point behind inner-city rivals Atletico Madrid, who top the table.
Meanwhile, the European champions are 20th in this season's Champions League table having lost three of their six games so far.
Less than 24 hours after his trip to Lancashire, Jude posted a selfie on Instagram of him enjoying his holiday abroad in Dubai.
He was then confirmed as the EA Sports LaLiga player of the month for December on FC 25 - for which he is the cover star male athlete.
Jobe meanwhile joined Sunderland from boyhood club Birmingham in the summer of 2023 and has been a regular in the first-team having amassed 66 appearances for them.
The 19-year-old midfielder has four goals and three assists in 19 Championship appearances this term with Sunderland fourth in the table, four points off an automatic promotion spot.
As for Shearer, Bellingham's antics paled in comparison to his recent trip on a train with Sunderland fans.
The Georgie king booked himself on a train with hundreds of Black Cats on their way back from a 3-1 win at Portsmouth earlier this season.
Recalling his hilarious trip up on The Rest Is Football podcast, the former striker said: "I was at a wedding in Italy and we came back on the flight on Saturday. We had to wait in the lounge for about four and a half hours before the flight back up to Newcastle.
"We'd been sat there for three and a bit hours and it comes up on the board, flight to Newcastle cancelled. I was absolutely raging.
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"I go to guest services, then to gate 17 to make sure there were no options. There were two other flights that evening but no spaces.
"By this time they've booked me on a flight today at 2:30pm. I'm thinking 'no, I've got to get home as it's my son's birthday and Newcastle are playing'.
"Me and our friends were scrambling to think what we were going to do. We look to get the train and they're all fully booked. Then one becomes available at 7:30pm. 90 minutes to get from Heathrow to Kings Cross.
"There was a lovely lady from LNER who said there were hardly any seats left, but said she'd do her very best.
"Bless her she got us enough seats. She got us onto the carriages and said it's going to be really busy as this is the only train on a Saturday night and said unfortunately there's going to be a load of football fans."
Laughing, he continued: "We're in coach C and I think 'oh my f***ing god… Sunderland played Portsmouth away'.
"I've got my cap on and I'm wedged in the corner and on they come and it's getting busier and busier. There's not one seat spare.
"The whole of the aisle is taken up with Sunderland fans and they're all p*****. They have bottles of beer.
"Within half an hour, I'm scared to lift my head up. They start signing the Newcastle songs. Then they start singing the Shearer songs. I can't even sing the other songs. I had four hours, my neck is killing me. I couldn't lift my neck up. I had my head down for four hours.
"Half of them got off at Durham and half stayed to Newcastle. I was petrified to get off. There was not one person who recognised me. I didn't move for almost four hours and I didn't get recognised.
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"They sang and abused me for nearly four hours and they didn't even know I was on the train. My friend said 'Al, why don't you walk through the middle of them and ask them if they want a drink?'
"It was an absolute nightmare. So for all you Sunderland fans travelling back on Coach C. F*** you."