Mario Gotze's father says there is little the Borussia Dortmund playmaker can do until a treatment plan for his metabolic issues has been devised.
He revealed that a strategy to treat the problem, which is keeping his son out of action indefinitely, will be established soon.
Gotze has not played in any of Dortmund's last seven matches after a metabolic disorder was discovered via thorough tests that had been ordered to investigate repeated muscular problems suffered by the 24-year-old.
"At the moment Mario is OK but there is not much he can do besides sitting at home and waiting," father Jurgen Gotze told Bild.
"There is no plan for the therapy and the exact treatment he will get will be decided shortly.
"We all have to be patient. He has to get going now."
Dortmund are on fine form without Gotze, winning three straight Bundesliga matches and scoring 12 goals in the process, but head coach Thomas Tuchel has backed him to become an important member of the team again on his return.
But they are also without key winger Marco Reus for the home leg of their Champions League last-16 tie against Benfica on Wednesday, which they trail 1-0.