Unfortunately many people let their bunnies go way too early
I second A&B in getting the baby bunny seen by a rabbit savvy vet to ensure that he’s in good health and also gauge his age. Depending on how old he is he might still need to be on a milk replacement diet. Don’t give him any fresh vegetables until he’s a few months old.
Also just a thought – could those people be allergic to the hay instead of the bunny himself? There are lots of people who thought they were allergic to bunnies at first but found out later that the allergy was actually due to the hay (usually timothy) or the dust that comes from the hay.
For the jealousy part, bunnies are territorial animals and since Wall E was the original bunny, he probaby felt threatened by this new addition and hence feels the need to mark. It’s common for bunnies to suddenly turn aggressive or distant and also lose their litter habits once their territory has been “invaded”.
Bear in mind that since Euro is still a baby, you won’t be able to know the gender till a few months later. He may be a she and you really don’t want an accidental litter. Bunnies can get pregnant at a very early age and it’s very dangerous for a young bunny to have a litter, so do keep Euro and Wall E separate at all times (they can’t even meet for playdates). Even if Euro turns out to be a boy, you’ll still have to keep them separate because two bunnies of the same gender are very likely to fight if they are not bonded. Make sure to block all access – they can’t be “wriggling” to each other.
To bond then you need to get both bunnies fixed and then go through a prebonding and bonding process (check out the BUNNY INFO or BONDING forum section for more info and to read out other people’s experiences with bonding bunnies) 