Disability has much to teach us about humanity - much more than science or religion ever could, because of the way it tests our character. As the disability rights campaigner, model and athlete Aimee Mullins points out, Darwin has been misquoted. He actually says it is not the fittest, or the strongest, or the cleverest - but the most adaptable -that survives.
Certainly, that is what a little girl called Isobel - my first child - has taught me, and she's only three-and-a-half.
When I was expecting Isobel, I told my husband Miles that I would love our baby, no matter what. We agreed that if she had a disability she would grow up unashamed of it. We would create a secure, loving family environment that taught her the value of being confident and unafraid to assert herself.
We both thought like that because we had ourselves grown up deaf. We had a positive attitude towards disability not because we felt we had to - but because it was all we knew. In our world, everyone had their own sense of normality, and ours was living as deaf people.
As artists, Miles and I had collaborated with disability artists in innovative grant-funded projects that explored how we could use our own diversity to drive creative solutions in architectural and interior design. Some involved mainstream architects and planning officials. But although we valued the insights our disabled collaborators gave us, we saw ourselves as a world apart.
We labelled ourselves not as disabled, but as deaf - inextricably linked to a community whose social and cultural values intersected with a shared language of our own - British Sign Language. Few other disability cultures - if they existed at all - had this distinction.
I see now that I was more prepared to bring up a deaf baby than a disabled one. I just didn't realize my thinking at the time.
With a deaf baby, we'd instantly have contacts who could work with us to ensure all her needs were met. We'd know who to talk to about ongoing issues, and explore our options with web resources we were already familiar with. Other types of impairment - and the adaptations they required - were too diverse and numerous for me to comprehend.
I cannot lie; the first 12 months of Isobel's life were awful. At 12 hours old, she had her first seizure - setting the scene for months of anxiety, fear, despair and sadness that endured far beyond her first hospital stay as a newborn. That day, it seemed that everywhere I looked, there was nothing but a thick, suffocating blanket of blackness. I couldn't see a future, or even a tomorrow.
The seizure was the first sign that Isobel had had a brain injury, the consequences of which would remain unknown for the next 12 months. From six months onwards, she was in and out of hospital every week with up to 60 seizures a day while doctors battled to bring them under control.
Life went blank, like the walls of the children's ward we often found ourselves in. While the day wore on, visiting doctors blended into one another and I'd listlessly watch the sun's reflections sweep the floor. Every hospital emergency was the same, because the reason was always the same.
Meanwhile at home, Isobel's developmental delays encroached more and more on my mind. I can never forget the way her four-month-old arms shot out like a Dalek's when she was playing in her bouncer. She'd take forever, too, to upgrade to sitting. I was convinced there was more to this than the effects of an extended hospital stay.
Scarier than the notion that my little girl could have a disability was the uncertainty of what it was. I started talking about Isobel having epilepsy, even though I knew that was a symptom of her brain injury, rather than the outcome. I desperately needed a label so I could move on, instead of dwelling on what on earth was happening in her head.
But when Isobel was finally diagnosed with cerebral palsy and global developmental delay at one year old, I found myself dealing with extraordinarily complex psychologies. Yes, I had a label; but it wasn't what I expected.
I didn't expect my reaction to the diagnosis either. As soon as the tears erupted, I raged against my grief for Isobel. How could I possibly mourn a living being, when I knew many high-achieving and positive role models who had cerebral palsy?
Essentially, I had to understand the reality of parenting a child with a disability - the initial shock, grief, anger, depression, the overwhelming sense of injustice - before I could move on. I had to go with what my heart was begging me to do, even though in my head, I couldn't see the point.
Knowing lots of people with cerebral palsy didn't mean I knew how to best support Isobel. I had to go on a crash course, reading as much as I could on the various types of CP, and talking to people constantly. The Internet became my best friend. I'm convinced that I was ultimately able to meet my parenting challenges head-on because I was already comfortable with the presence of disability in my life. In that respect, I was already a little further along my journey than parents with no prior experience of disability.
Having said that, Isobel's epilepsy did scare me, not only because of the risks it presented to her cognition but also her life. If she had continued to have 60 fits a day the consequences would have been devastating.
Thankfully, the seizures evaporated - just before hope did - when Isobel was 15 months old. They have not reappeared since, although she continues to take anticonvulsants regularly - and at this stage, we are still not 100 per cent sure they will stay away for good.
Of course, those seizures are part of an enormous maze that we are only now - three-and-a-half years down the line - beginning to navigate with confidence. For a while the older Isobel got, the more twists and turns her development took, and each one forced us into new territory.
First she was hemiplegic; then in March last year an MRI scan revealed her to be quadriplegic, with a question mark still hanging over her cognitive abilities. Would she speak? Would she sign? Would she sit, stand or walk? More importantly - would she ever stand up to the oppressors she was sure to meet in her lifetime?
Sometimes, just when we thought the answers would come, they never did. Isobel would take 48 steps forward one day, and give way the next. One day she could pull herself up to standing, and the next she couldn't. And so the cycle of hope, despondency, and grim acceptance went on.
Today that cycle continues with far less intensity than before. Instead of wallowing in disappointment, we shrug off new setbacks for another day. When progress does surge, so do our hopes - albeit tempered with caution.
Essentially, my perspective of disability has changed. It's richer than before. Although I had accepted people with disabilities for a very long time, I didn't really talk to them about their disabilities. I didn't have an incentive to, unless we were exploring diversity and inclusion as part of a project. They were just other people in my life - people that I enjoyed getting to know.
Isobel has taught me so much about her disabilities. There was a lot I didn't know about CP and epilepsy before she came along. I'd never even heard of global developmental delay or microcephaly, which she also has. By learning about them, and the work she has to put in to overcome them before she can start meeting her developmental milestones - albeit at her own, very individual, pace - I've come to appreciate much more the invaluable contribution disability makes to humanity.
For me to say that I'm more knowledgeable about CP or epilepsy or even global developmental delay than my daughter would be preposterous. Isobel is the expert of her disabilities, not me. I am still only learning about them, whereas she learnt to live with them from day one. Just as being deaf is our normality, having CP is hers.
It's this that enables Isobel to adapt to her environment with the cool acquiescence of a Darwinian animal - and that's why she has taught me so much more about what it means to be human than I could ever teach myself.
The original version of this post can be viewed in BLOOM.
Follow Melissa Mostyn-Thomas on Twitter: www.twitter.com/melissamostyn