Latoya Anderson's application for Prince-Daniel Chambers' passport took three month longer than his dad's and after 13 calls to the passport office, the parents were told "security issues are responsible".
Although the mother has now received the passport back, she wants answers about why her son was treated this way.
Anderson told the Sunday Mercury: "To us, it feels as if our baby has been treated like a suspected terrorist."
Anderson and her husband Donovan moved to Birmingham from Jamaica 16 years ago, and worried the delay in their son's passport application would ruin their £4,500 Jamaican holiday.
Anderson's nine-year-old daughter, Shanice, also had no problem getting her passport application accepted.
However when offering to go into the passport office to find out why her 20-month-old son's passport was being stalled, the mother-of-two was told nothing could happen until the "necessary security checks" had taken place.
The parents approached Birmingham community activist Desmond Jaddoo and Sutton Coldfield MP Andrew Mitchell to prove their son was not a security risk.
Anderson told the Birmingham Mail: "It’s ridiculous. How can there be any security concerns about a baby? We have asked time and again for details of the security concerns, but received none."
The Birmingham Mail contacted the Passport Office on 10 July and received an assurance that the document will now be on its way.
The Voice newspaper also claimed they contacted the Passport Office on the same day, and were assure the application would be processed as soon as possible.
Anderson told The Voice: "I’m well aware that the Passport Office warns people not to book any travel until they have the document, but it would have been impossible for us to leave it any later to fly to Jamaica in August during the school holidays."
Jaddoo said the situation was "laughable".
Stating that a child's first passport should take three weeks, he told the Birmingham Mail: "I am unable to understand the additional security checks that are required for this 20-month-old child. Clearly, this is totally unacceptable."
The activist said the issue is to do with transparency.
After hearing Jaddoo's comments, the Passport Office wrote him a letter to him, which simply stated that the security checks were necessary to enhance the trust in the British passport and international border agencies.
A spokeswoman for the Home Office issued a statement which said: "Before issuing a child’s passport, a number of safeguarding checks are required and this can mean applications can take longer than those for adults."