Hello Jo
I would strongly advise you contact your nearest carer to get this new one checked out. It will almost certainly have at the least a parasite burden that may need treatment,
Regarding putting them together afterwards. The stress may cause problems for the hog you already have, which I assume you haven’t had checked over?
Hogs in captivity will often do very well together, but not alway’s. One can be a bully and prevent the other getting food or they can fight so you would need to monitor/weigh
You also need to sex them, It’s rare for them to breed in captivity but not unheard of.
Do not put them together until you’ve seen a carer please
