Weird! Third horn?

[Nanno]

Hmm... Are you sure it's sprouting separately and not part of the left horn? Look very closely at the base and see if it looks like it attaches to the left horn. At this age, baby goats' horns lose their soft outer shell, which peels away and can look like a separate horn, or look like the horns are splitting in two.

I'm sorry these boys haven't been very healthy. How old are they? Are they bottle kids and were they weaned when you got them or still on milk? It's common for bottle babies to be less robust than dam-raised kids.