Megan and Lisa Donahue, from North Carolina, started their transformation project as a way to spend time together, but it soon took on a deeper meaning.
In 2015, the family was rocked by the loss of youngest child Michael aged just 15.
The youngster was killed in a devastating road accident but left an enduring legacy.
Mum Lisa told Euronews: “Michael loved nature, he literally was outside morning, noon and night.
“If he could live in a bus, it would be his perfect situation.”
Megan was inspired by his outlook on the world and his motto: “It’s the simple things in life that make it worth living.”
This led her to start work on converting her first school bus, or “schoolie”, into a tiny home in 2017, which she dubbed Gus.
With just about 75 sq ft of living space in each one, it’s a challenge to make them feel spacious, but she manages just that.
Lisa helped out and now they have built the hobby into a business and try to honour Michael’s memory and spirit of fun.
She added: “Our main reason why we’re doing this, too, is we want families to know how important it is that they spend time together – because you literally don’t know if you have tomorrow.”
Since Gus, the pair have created Agnus, Brutus, Julius, Marcus, Phillus, Willus, Spartacus, Tobius and many more.
Once the buses are completed they are sold on, but Lisa and Megan are selective about who they sell to as, to them, the vehicles represent Michael.
Megan said: “These buses are such a gift. I can’t imagine where I’d be without them personally.
“I’m just too happy right now doing this to stop it, so until I’m not happy anymore then it’ll be my job.”