en_tn_condensed/mrk/05/40.md

The child is not dead but sleeps." They laughed at him

Jesus uses the common word for sleep, and so should the translation. The reader should understand that the people who hear Jesus laugh at him because they truly do know the difference between a dead person and a sleeping person and they think he does not.

put them all outside

"sent all the other people outside the house"

those who were with him

This refers to Peter, James, and John.

went in where the child was

It may be helpful to state where the child is. Alternate translation: "went into the room where the child was lying" (See: rc://en/ta/man/translate/figs-explicit)