Identical twin brothers speak 26 languages each — including one they invented as toddlers

Identical twins Matthew and Michael Youlden can speak 26 languages — one of which can’t be found in the annals of etymology.

Inspired by the multicultural landscape of their hometown of Manchester in the UK, the polyglots who now run their own language learning company became interested in foreign language studies from an early age.

Their first language, however, was all their own: Umeri.

“Umeri isn’t ever reduced to a language used to keep things private,” the identical twin brothers told the BBC in a joint message. “It definitely has a very sentimental value to us, as it reflects the deep bond we share as identical twins.”

The Youldens can’t remember a time before Umeri, recalling as preschoolers their confused guardians as the boys cracked inside jokes in twin speak.

Spanish was their third language, acquired on a family vacation when they were eight years old, followed by Italian and Scandinavian languages — all the while studying and developing a grammatical structure for their own homegrown language.

An estimated 30-50% of twins create a unique form of communication, a phenomenon known as cryptophasia, per the BBC.

While deepening the relationship between twins, such exclusivity can be alienating.

“Twins have this shared language, that at some point they stop using, as if they feel ashamed of it,” Matthew told the BBC. When he and Michael would convene in Umeri, their friends and family shrugged: “They’re off doing the language thing again.”

Nancy Segal, director of the Twin Studies Center at California State University, warned parents of twins who exhibit private speech patterns that these habits can have a negative social impact. “One problem with twins is that parents tend to leave them alone because they entertain each other, but then they don’t have adult language models,” she said.

Such was the case of Barbadian twins June and Jennifer Gibbons, who grew up in Wales in the 1970s. The sisters were bullied from a young age for a shared speech impediment and became so antisocial as a result that they vowed only to speak to each other.

By age 19, their speech was incomprehensible. The troubled sisters took up a life of crime before they were captured and committed to a high-security psychiatric facility in Broadmoor, England.

“We were desperate, we were trapped in our twinship and trapped in that language, we tried everything to separate ourselves,” said June in a 2023 BBC podcast about their lives.

There are few reliable case studies on twin-speak as most twins forget their special languages, according to Karen Thorpe, who studies language development in twins at the University of Queensland’s Brain Institute. However, many will retain special nicknames and non-verbal cues that only the twins can translate. “They might not have something that we would call an exclusive language, but they do have something that’s quite special,” she said.

Segal agrees. In general, she told the BBC, “twins do not invent a new language, they tend to produce atypical forms of the language they are exposed to. Even though it’s unintelligible, they still direct it to other people.”

While Michael and Matthew don’t intend to pass down their language, they have continued to develop and fine-tune Umeri for themselves.

“It’s one of those things that unfortunately does have an expiry date to it.”