it means that the son add extra things when he was talking about his dad.
for example the father said that he would like to take a day and relax.
and maybe the son says that the father said that he would like to quit his job and explore the world.
"half the crap" this means that a lot of what the son was saying was not true and, that not even half of it is true. This is more of a saying than a literal expression.