The family said the proposed adaptations would make it easier for Sid to move around the property and access his bathroom and bedroom.
Sophie said doctors had warned them he might not live beyond the age of two.
“It has been a really difficult time,” she said.
She said securing support for her son had been an ongoing struggle.
“Everything along the way has been such a fight,” she said.
“A fight, to get equipment and fight to get the care that he needs, the fight to get access to different treatments and therapies.”
Although treatments are available for SMA, there is currently no cure.
A spokesperson for Maidstone Borough Council said: “The council is working with the family to progress disabled facilities grant applications and support them in accessing all available funding.”
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