The four-year-old's skin is so sensitive to sunlight that he is extremely susceptible to skin cancers.
He stays indoors as much as possible, but if he does go out, his parents, Isla, 34, and Craig, 40, slather him with Factor 50 sunblock.
Alexander has a rare condition called albinism, which means he has very little pigment in his skin, hair and eyes.
He wears glasses because he is partially sighted and suffers from involuntary eye movement and photophobia.
The family home in Kelty, Fife, Scotland, is also fitted out with dark blinds to keep out the light and their car has tinted windows.
Isla said: "He wears a big hat when he's outside and can only see his feet, he'll never be able to drive a car but he has enough vision to get around.
"Because he's got no melanin, the way his eyes are connected to his brain is quite different, which has an impact on what he sees as well."
When Alexander was born Isla said she was shocked, as unlike his older siblings Matthew, nine, and Bethany, six, his hair was white, his skin was pale and his violet eyes were tightly shut.
"My other two children were born with dark hair, we had no idea we had the albinism gene," she said.
Isla said one of the hardest things about the condition was dealing with others comments.
"What I've learnt is most people are just curious and my response is to be positive," she said.
"He's not fussy about people asking him because he doesn't want to be different. We've taught him to be patient and kind about it, but it will get harder as he gets older."
Alexander will start Kelty primary school in August and the school have been adapting lighting and putting up UV shields for him.
The family are looking at white stick training and guide dogs for Alexander and are thinking of sending him to Edinburgh Royal Blind School when he's older.