It was the fourth time a Watford player has been sent off this season.
Silva was disappointed with the result, with Watford losing 4-1, and he knows that his players cannot continue to lose their cool in such a manner. But he does not believe it is a squad-wide issue.
"No, I am sure about that [disciplinary issue]," he said.
"Until now you can talk about the red card for Miguel Britos [against Brighton in August]. I agree in that moment, but for the others I am sure we don't have an issue."
Luckily for Watford, the red cards have not stopped the team having an impressive season.
The club is currently in 9th place in the Premier League, and seven points clear of the dreaded drop zone. In the coming games, Watford face Brighton, Leicester City and Swansea, before going to Manchester City in the new year.