Who are four of the main characters Milkweed and a brief description them?

You're likely referring to the novel *Milkweed* by Jerry Spinelli, which tells the story of a young Jewish boy in Warsaw during World War II.

Here are four of the main characters and brief descriptions:

* Misha: The protagonist and narrator of the story. He is a young Jewish boy who is orphaned early in the war. Misha is resourceful, resilient, and often clings to fantasy and make-believe to cope with the horrors of his surroundings.

* Janusz: A young Polish boy who initially helps Misha survive by acting as his protector and friend. Janusz has a difficult home life and his loyalty and kindness are tested by the pressures of the war.

* Uri: A Jewish man who acts as a father figure to Misha and other orphans. He is a wise and compassionate man who tries to instill hope and faith in the children despite the bleak reality of their situation.

* The "Angel of Death": A mysterious figure who appears throughout the story. The Angel of Death is a symbol of the ever-present danger and fear that surround the characters. He is both a real person and a metaphor for the forces of violence and destruction that are overtaking their lives.