I parent my 4 year old grandson and have done since his birth. His mum lives close by with little sister (different dad), they have a good relationship and see each other most days. I have a child arrangement order with residency as requested by children's services when grandson was a year old - mum was just 18 when grandson was born and I had adopted her from the care system aged 8 - she has alot of emotional scars. Anyway dd slept around and is not quite sure who dgs father is however she has steadfastly named a certain boy as being the most likely. This boy now lives in his country of origin and has never shown any interest in meeting dgs. Anyway right out of the blue a couple of days ago someone else got in touch with dd suggesting he thinks he is the father. DD had blocked many of her old crowd of friends (we moved away to get away from them) from all her social media years ago. He produced a pic of himself at a similar age to dgs and there is a very striking resemblance and I think he most likely is his father. Now this person is presently in prison awaiting trial for a nasty street robbery. It is possible that he is trying to preempt a deportation order post sentence by getting in touch now, though DD thinks he was born here so maybe not. He wants a paternity test. I'm happy to give permission for this as I feel my grandson has a right to know who his father is. My question is, if he we do our own dna test through a home kit, is this guy able to do his swab in prison. Is this allowed? Does he need permission from someone. I have no intention of going through the courts at this stage - though it may come to that further down the line if he starts wanting regular contact and I'm not happy with that. Any advice greatly received.