OTTAWA - A 53-year-old woman and her 35-year-old son pleaded guilty to incest Thursday after a horrified family member caught them having sex.

The mother and son - who can't be named because of a publication ban to protect the woman's daughter - each received a suspended sentence and probation.

The court heard that on May 14, 2010, the brother and sister, along with their mother, were visiting their dying father's Byward Market apartment.

The sister stepped out on a balcony to have a cigarette and happened to look through a window into a bedroom.

She saw her brother having sex with her mother, whose skirt was hiked up around her waist.

"I'm going to refrain from making any moral comments or moral evaluation of your conduct," Judge Paul Belanger told the woman.

"I think your conduct speaks for itself, particularly as a mother. I'm going to leave the opprobrium to your own conscience.

"Above and beyond what I might do the ostracism of members of your family and perhaps others in society will be significant punishment for you."

Her son's lawyer had argued that his client was a victim as well as a perpetrator, and had been removed from his parents' home by the Children's Aid Society - a charge the mother denied.