I am sure
@furryfriends (TEAS) will have plenty of advice as she has much more experience than me but a lethal piggy can live a full and happy life as long as it's needs are met. They will likely have a shorter than average lifespan but that need not be too short! I know many who have lived to around 4 years old and my Hamish who is very mildly affected turns 5 this summer and shows no more sign of slowing down than his normal, healthy brother Angus!
The care your piggy will need will depend on the particular problems it has. All lethal piggies are different but they will show some or all of the following: blindness/partial sight with smaller than normal or missing eyes, hearing loss, dental issues and internal/digestive malformations (these are only usually noted on autopsy and are usually unknown in life). They may need regular dental work, food prepared in a certain way to help them eat if teeth are missing etc. But in many ways their care is much like that of any other guinea pig. They need food, water, shelter and love! They can absolutely share their cage with other piggies as long as they are tolerant of their differences but don't worry as guinea pigs don't worry about disability in the same way humans do, they just get on with it!
It is important that you have access to good quality vet care, particularly for any dental issues. Simon Maddock @ The Cat & Rabbit Clinic in Northampton is who Furryfriends uses and he has probably the most experience of lethal piggies of any vet in the UK... Indeed many have never heard of it as it is often only mentioned in passing in vet school and many are under the impression that all lethal gene piggies die at birth, as many of the most severely affected do, so never consider those who go on to live with a variety of disabilities.
Check out TEAS website and their youTube channel to see some lethals living life to the full....
The Excellent Adventure Sanctuary
Feel free to PM me if you want to ask things and I will do my best to answer where I can. Well done for taking on this wee one and we wish her all the best x