Gay rights groups celebrated a landmark court ruling yesterday, while family values groups said the decision to give a London boy two moms is an attack on the traditional family.

The boy's father, who sees his five-year-old son regularly, was "thrilled" but didn't want to comment until he had spoken with the boy's mothers, who are on vacation with the son, said Alf Mamo, lawyer for the father.

"After three years of being in the court system, he's happy to have his son's reality recognized," Mamo said. "The decision reflects the dignity of the non-biological mother, which she deserves as a full participating parent in the family."

Gay rights organization Egale Canada says the ruling by the Ontario Court of Appeal recognizes the reality of lesbian couples who are already raising children with the father's involvement.

But supporters of traditional marriage and family values warned the decision offered a "watered down" interpretation of family and could open up the possibility of multiple parents, perhaps as many as six, for a child -- and unforeseen legal headaches if those relationships fail.

"Something that is a social policy decision certainly shouldn't be decided by one courtroom," said Dave Quist, head of the Institute of Marriage and Family Canada.

The government should "hit the pause button" on legislation involving three-parent families as well as same-sex marriage, in-vitro fertilization and stem cell research, to give a commission time to evaluate such issues, he said.

"This will certainly impact everyone in Ontario if it is not appealed."

Locally, the 400-member traditional family values group Citizen Impact also hopes for an appeal .

"It is a situation with lots of ramification and it should have been decided in Parliament," said Jack Baribeau of Citizen Impact.

Citizen Impact has opposed the move to grant mom status to the boy's non-biological parent since 2003 when the case was first heard in a London courtroom.

At that time, Judge David Aston dismissed the application from the same-sex couple on the grounds he didn't have the jurisdiction to make the declaration sought.

The appeal court found recent rulings that have "moved toward a broader discretion, under the impact of changing social conditions and the weight of opinion."

Baribeau said the court was "stepping beyond (its) boundaries."

"I'm not saying individual situations can't be OK. It's just not what's best, as an ideal, and the laws need to reflect what's best," he said.

Former London MP Pat O'Brien, who left the Liberal party over the same-sex marriage issue, said he was disappointed by the ruling.

"Words like mother, father, marriage -- could they become meaningless?" he asked.

O'Brien, who is retired but works as a consultant in hopes of getting the government to reverse the same-sex marriage legislation, said the court went beyond its jurisdiction.

But Mamo disagreed.

"The court was able to find a solution in the situation where they acknowledge the legislation does not contemplate the circumstances," he said. "The reason we have a charter is to hold values of individuals as being higher than politics. These decisions are too important to be left to the whims of any particular party or consideration of the cabinet of the day."

He scoffed at the suggestion such a ruling could lead to confusion with multiple-parent families.

"Wouldn't that be wonderful if we see people lined up wanting those responsibilities that a parent has? I really don't see that happening, though."