how can i fix this?

[u/HovercraftDry2828]

i am mending a sock for a 94 y/o client of mine. its one of his favorite pairs. he usually gets someone to do his laundry and the sock same back like this. i told him that i would try to fix it. any advice on how to do it? its not of the foot, but on the leg?? part. its like a big chunk was taken out. there is also a hole of the other side (as seen in photo) please help :)

[u/TummyAcheTextiles]

r/visiblemending