A nun has caused an outcry at a Catholic High School in Charlotte, North Carolina, after she gave a guest lecture saying homosexuality occurs because parents are divorced or single.

Administrators from the Charlotte Catholic High School on Wednesday evening met with over 900 parents who were outraged by the lecture given by Sister Jane Dominic, a theology assistant professor at a Catholic college from Nashville.

A petition was started by students from the school, which gathered over 4,500 signatures. It rejects her suggestions that homosexuality mainly occurs as a result of divorce, or from single parents, and porn.

A counter petition was started, now signed by 1,800 people, which defends the nun’s speech, and is titled ‘Stand up for Catholic Beliefs’.

The Change.org page states: “[Sister Dominic] shared with us the beauty of masculinity and femininity, and how this affects each of us as we grow and develop. She soon entered topics very controversial, yet topics that need to be taught. This is our platform.”

Some parents said if they had been told about the guest lecture in advance, they would not have allowed their children to attend.

Regarding the speech, David Haines of the Catholic Diocese of Charlotte said: “I think one thing that will come out of this is there will be an understanding parents need to be notified, but how exactly is that going to take shape?”