She said he previously had no propensity for profanity.
"The thing I'm most upset about is I now have a swearing child," Ms Houghton said.
"I feel at least an apology is in order."
She called the Hastings restaurant to complain but the manager said he had no idea what she was talking about.
"I was quite shocked he knew nothing about it, as it has been big news of late."
The toys have been creating a fuss in America, with a number of parents complaining about them.
Minions are the little yellow creatures introduced to the world in the children's movie Despicable Me. The director of Despicable Me, Pierre Coffin, who co-created the "Minionese" language, said that the toy could be saying literally anything.
"I'm not saying what people with a twisted mind seem to be hearing," Coffin told American website Mic.
"If it was my intent to say inappropriate stuff, you'd hear it, I promise you. But I'd be pretty stupid doing it in a movie for all audiences including kids. I don't think myself as being very intelligent but I'm certainly not that dumb," he told the website.
People continue to debate whether the sounds are swearwords or the Minion's indigenous gibberish.
McDonald's refused to pull the toy, saying the Minions are speaking their own language.
Ms Houghton has also called the national head office but was yet to hear back.
"They should be pulled off the shelves. It's not on for kids to be hearing that sort of thing."
McDonald's head of communications Simon Kenny said it was just someone hearing something that wasn't there.
"Some of the Minion toys currently included with Happy Meals make sounds which are Minionese," Mr Kenny said.
"That specific toy says 'para la bukay', 'hahaha' and 'eh eh'."