Who kills Tybalt and why?

Tybalt is Juliet’s cousin (Which makes Tybalt a loyal
Capulet) While Romeo is a Montague (A sworn enemy to the
Capulet’s)

Romeo is pressured to go to the Capulet’s ball
and is seen there by Tybalt who asks Mr. Capulet if they can throw Romeo out and fight
him. Lord Capulet says no, that Romeo is a respectable man and that he can
say.

Tybalt is still furious at this, and, two days later,
Tybalt sees Benvolio and Mercutio (Benvolio’s foil) Benvolio is a calm man and Mercutio,
is well, not. When Tybalt sees Benvolio and Mercutio, he approaches them looking for
Romeo Montague. When Romeo shows up, an in-law to the Montagues now, he sees Tybalt and
approaches, Tybalt insults Romeo in front of everybody and Romeo shrugs it off since he
is married to Juliet now (But only Friar Lawrence, Nurse and I suppose Romeo’s servant
Balthasar know other then the husband and wife)

When Romeo
walks away, Mercutio steps up to fight Tybalt, Romeo tries to stop the fight since
Mercutio is Romeo’s best friend and now Tybalt and Romeo are now Cousin-in-law. But,
Tybalt, being a professional sword-fighter, he stabs Mercutio when it is very
un-expected.

Benvolio takes Mercutio away after Mercutio
died, while Mercutio was dying however, he foreshadowed: ‘A Plague on both your houses’
Romeo cries and gets angry at Tybalt for killing his best friend. If Romeo controlled
his temper, Tybalt would have been in trouble, but, Romeo fights Tybalt and kills him,
now Prince will have to kill Romeo, Romeo runs to Friar Lawrence to hide. Thus the
climax starts to take off.

With Love and
Care,

Alice.