Like most any nine year old boys, Leo Le Gal is crazy about Lego. And for his mum and dad, every moment they spend playing with their son is a precious one. Leo has the life-limiting condition Duchenne Muscular Dystrophy.
But, thanks to him taking part in an American trial of a drug called Translarna, the devastating symptoms of this muscle wasting condition have slowed down.
Ruth La Gal, Leo's mum says: "In the last five months now we've seen no kind of deterioration at all, in fact his condition has completely stabilised which is fantastic news, we've really seen no worsening in his symptoms in that time and although the medication isn't designed or intended or able to restore function that's been lost so we haven't seen him miraculously leap up and start running around it has stabilised his condition which is a fantastic thing for us because it means he is no longer getting any worse."
However, it's not known how long Leo will be able to take this drug as it hasn't been approved for use by NHS England.
Ruth says: "It's very important for all children who need this medication to have it as soon as possible, it is absolutely vital. Children with Duchenne get weaker on a daily basis so every day those children are without medication, that's a day that their condition worsens. I would say that families that don't have access to this drug yet will be very, very anxious, they'll be desperately wanting their children to get hold of this drug and be able to start taking it."
When Leo was first born there were no signs anything was wrong - it was when he was five and a half symptoms began to show. The Muscular Dystrophy Trust says Transarna offers a huge breakthrough.
Robert Meadowcroft from the Muscular Dystrophy Trust is critical of the time the NHS is taking to approve its use: "We've been pushing and pressing NHS England for months over this and it seems what has happened is a straight forward simple administrative bungle which has led to the present impasse they knew there was a drug coming through, they knew they had to speed up the process and frankly they've made a complete hash of this that needs fixing."
In a statement, NHS England said: "NHS England does not currently routinely fund the use of Atularen (Translarna) for patients with Duchenne Muscular Dystrophy. However a new draft clinical commissioning policy covering its potential use has been developed in collaboration with a range of stakeholders, including patient and carer representatives, and taking into account the currently available evidence on clinical effectiveness. This draft policy continues to be one of a number of new draft policies being considered as part of NHS England's funding prioritisation process for 2015/16."
Leo's trial of Translarna ends in 2016 - his family's hope is that before then, the drug will be licensed for use in this country - for Leo and the thousands of people suffering from this cruel illness.