Twenty. You counted the same horses coming and going

Sand

False. Some cogs may be pabs, but not definitely all of them.

A cold.

Trust.

At the back of the train. By the time she reaches the start of the tunnel the train will have accelerated and will now pass through the tunnel faster.

The only one who is lying for sure is Philip. Hans speaks probably the truth and
Emanuel lies. It can be also the other way, but since Hans expressed himself before
Emanuel did, then Emanuel’s remark (that he does not know whether Hans is lying) is
not true.

Romeo and Juliet are fish. The rumble of the train knocked the tank off the shelf, it broke and Romeo and Juliet did not survive.

Nine.

Gum.

Johnny (given in the question Johnny's father. so the fifth son is JOHNNY)

Trouble.