Christine and Iain Agnew are keen to support Scotland's language and so sent son Archie to a Gaelic nursery school in Anniesland.
But the four-year-old has now been denied a place at Glasgow Gaelic School.
Christine, 39, said: "My son has been going to a Gaelic nursery for the past two years.
"To get into the Gaelic school they say you have to show commitment to the language.
"Well, I'm not sure how else I could have shown that commitment.
"We haven't been given a straight answer as to why Archie has been refused a place and I would really like the council to reconsider."
Christine, from Clydebank, said she has lodged an appeal, as have two other mums who are in a similar position.
But she believes there should be enough primary provision in the city to accommodate all children who are in the city's Gaelic nurseries.
Currently, a second Gaelic primary school is planned for the South Side of Glasgow but Christine said that will open too late for Archie to attend.
She added: "I want Archie to learn Gaelic because he's Scottish and that's his language.
"His grandparents are from Skye and Tiree and speak Gaelic but, because my husband and I were raised down here, we never learned.
"I want to make sure my child has that chance."
But a Glasgow City Council spokeswoman said people who live outside Glasgow must make a placing request and not all can be accommodated.
She said: "All Glasgow children who wanted to get into the Gaelic School will have a place in the new term.
"This is a placing request from someone who lives outside the authority.
"Just because someone goes to one of our nurseries it does not guarantee them a place in one of our schools."
Glasgow Gaelic School -Sgoil Ghaidhlig Ghlaschu - was the first Scottish Gaelic school and caters for pupils from the ages of three to 18.
The 2011 census showed there was a slight fall in the number of Gaelic speakers in Scotland, from 59,000 in 2001 to 58,000 in 2011.
But more younger users of the language are expected as schooling options are expanded.
Last year only 6% of the six-year target for pupils entering Gaelic medium education had been achieved.
The Government-funded Bòrd na Gàidhlig (BnG) said the main aim of its National Gaelic Language Plan until 2017 is to increase the number of pupils entering the first year of Gaelic medium primary schools from 400 to 800.
The figure rose by only 28, or 6%, between 2012 and 2013.
The Scottish Government spends £25 million every year on promoting Gaelic.