Critics of abstract paintings like to denigrate such works by claiming they could easily have been created by a child. Now a Melbourne gallery owner has discovered there is truth in that old chestnut after he agreed to exhibit paintings by an artist who turned out to be a two-year-old girl.

Mark Jamieson, director of the Brunswick Street Gallery, was shown the paintings by Nikka Kalashnikova, a Russian-born photographer whom he represents. The artist's name was Aelita Andre, Kalashnikova said, omitting the fact that Aelita was her daughter, and a toddler. Mr Jamieson liked her work, and decided to feature it in a group exhibition opening next week.

It was only after he began publicising the show that he learnt Aelita's identity. "I was shocked, and, to be honest, a little embarrassed," he told the Melbourne Age yesterday. He hesitated about whether to go ahead with the show, but resolved: "We'll give it a go."

Mr Jamieson said it was difficult to judge abstract art. "There are different approaches," he said. "There is a formal approach and then there is a free-form approach that comes off a more intuitive base. And if you're thinking about the latter, perhaps a two-year-old can do it as well as a 30-year-old."

Aelita has been painting since before she could walk, according to her mother. Kalashnikova initially thought nothing of it, but last August, when Aelita was 19 months old, she became convinced there was real potential in her work. She gave her a canvas primed with red paint, and her daughter produced a painting that is among those about to go on show. Asked why she did not disclose the artist's identity, Kalashnikova said she and her husband, the artist Michael Andre, wanted the work judged on its own merits. "Of course, every mother is proud of their child," she said. "I didn't tell him [Mr Jamieson] because I had all these feelings going through my head – fear, embarrassment." The Age showed Aelita's paintings to its art critic, Robert Nelson, who was not given any background information. He said his first impression was of "credible abstractions, maybe playing on Asian screens with their reds". On learning the artist was a child, he said he was not surprised and that "credible" art could be found at any primary school.

Aelita's paintings will be priced from $300 (£140) to $2,000.