Fractured Tibia and Fibula with closed reduction (ankle, doctor, leg)

[Mercedes28]

So I have a question my son was playing baseball and this child that was running towards second base where my child was, he then slides and pushes my son off the base but then falls on his leg fracturing his tibia and fibula, also displacing his ankle.

The doctors realigned his ankle and he has a full leg cast. His graduation is coming up and his dance.

Can anyone tell approximately how long does he need the cast for.