my brother is 7 years old and he has a large liver and this saturday he has to go to the docters to
get blood taking and pictures of his lung
The above is correct, liver cysts are common. Most doctors take a wait and see approach to them with simple montoring of blood work and imaging.
Take care.
Cysts are fluid-filled sacks. They are very common. Most people never know they have them until they have a scan for an unrelated condition.