Netherlands manager Ronald Koeman missed the team's training session on Tuesday due to 'something' involving his wife.
Koeman, 62, married Dutch actress Bartina, 64, back in 1985.
Bartina revealed she was fighting breast cancer last year, having previously beaten the disease, but it is not known if this is behind his absence.
And Koeman boarded the team's flight to Malta on Wednesday ahead of a World Cup qualifier on Thursday evening.
He said: 'That had to do with my wife [missing a session]. You don't just leave. So if you do, it means something.