i have two guinea pigs one that is blind and about 5/6 years old and the other is about 2 this year.

I need advice on how to care form my oldest guinea pig. he is called elliot. he is abasinan tortleshell and white. he is blind in both eyes. he has a pussy lump on his back. he has 4 toes on both of this back feet (they shud have 3 toes). I got him about when he was about 1 1/2 years old. i got him to be a compaion for my rabbit, who is now died. He has been losing weight. first time i weighted him he was 2lb then when down to 1lb 12oz and now he is back up to 1lb 15oz. i weight him regular as well has the other guinea pig. Elliot lives with oscar and a neatherland dwarf. they get on really well with each other.

I just want so advice on how to look after him as he cant see where he is going. If you have any ideas please bring them forward.

Thanks for your time and help.