They are completely motivated by a desire to create change for their families and others, in a way that paid writers cannot match.
It's cathartic - the most common reason to start a blog is to be able to express yourself.
As one writer put it, blogging is a cheap form of therapy or counselling for many.
So often we find ourselves writing into the evening, tears plopping onto our keyboards, and working through the trickier emotions we so often face and somehow we 'blog through it', as if seeing the words on the page unscrambles what is in our heads and hearts.
Sharing information - Some parents share resources and tips on their blogs, others use the online space as a kind of diary to provide a running commentary with friends and family when their child is ill.
This reduces the need to keep repeating themselves and the blog acts as a hub of information.
It can also be a way of explaining difficult situations to loved ones when a face to face conversation might prove impossible.
Support and community - When I began my blog I thought I would be supporting new families with a baby with Down's syndrome.
What I very quickly realised was that my blog would serve as a portal into a whole online community who would help me through the toughest of days, the worrying moments and whose families would lead the way for us through example.
Blogging brings us access to a fantastic network of support and friendship and often supplies the answers we seek that we can access in small chunks whenever we are ready.
It reinforces that we are not alone.
Campaign work - Often the blogging community join forces to create lasting change.
Our voices are stronger and louder together, and we can see them put to good use working on projects such as calling for more accessible toilets, supermarket trolleys with support for disabled children or adapted clothing and larger nappies to be more readily available.
These, along with campaigns to educate the public and medical professionals about various conditions are having a real impact on the way families like ours experience life.
Fundraising - Another way in which SEND bloggers often join forces and work together for good is fundraising for their charities, as well as raising the profile of the work they do.
With social media and hashtags often going viral on awareness days, it can be a straightforward way to collect vital funds.