Emancipation because of Pregnancy

Hi, Great forum and very helpful too!
I have a 17 year old daughter that lives with her mother. I pay $187.00 a week in support for 3 girls all together(1 Mom). The 17 year old is now Pregnant and works part time. Her Mother made her quit school so she would not be teased at school. Why should a non custodial Parent have to pay support for a child who is not in school and has a job? This will greatly take money away from my other two kids to help the Pregnant one. I love my kids to death but Taking care of another Mans Child? That is where I draw the Line.
Any Advice would be Greatly Appreciated

Indiana Dad

Pregnancy does not result in automatic emancipation.

I understand that, and sorry if it seemed as if I was implying it. My concern is that the money I pay will not be used to care for my kids. The Father of the baby should be held accountable, not me. I care greatly for all of my Children, my concern is that I'll be supporting another child who is not mine.