"Your daughter looks like you."
Translation:Kızın sana benziyor.
Kızının means "your daughter's", i.e. something belonging to your daughter.
Or it could be "his/her daughter's".
Why is it kizin and not kizi? I am wondering because the "in" is already in senin?
kızı is "his daughter, her daughter". You can also say "onun kızı"
For "your daughter", the possessive ending is -(i)n, i.e. kızın or senin kızın.