Sorry to be the bearer of bad news, I can almost guarantee (anecdotally) that this idea won't work, sadly, though I MAY have thought of one way.
My sister in law was using my account when I wasn't. There's a long backstory here, suffice it to say Blizzard knew she was using the account and due to the circumstances, okayed it.
When she was finally able to reactivate her own account, she wanted to transfer her main on my account to HER account. Blizz was okay with it, again, given the special circumstances, even though we don't have the same last name, or even live in the same province.
We had to jump through a BUNCH of hoops to prove we weren't selling characters, but they finally let her transfer her one character to her account.
All the pets and mounts that that character had obtained, including Vial of the Sands (this was in Cata, JUST pre-MOP) went to the account with her toon, though copies DID stay on my account. (I'm sad that she didn't get a chopper while she was at it!)
Unfortunately, anything I had had previously, that she didn't already have, did NOT transfer over, and remained only on my account. A ticket submitted was answered with "working as intended", I got to keep the pets and mounts, AND achieves, she'd gotten on my account.
Tl;dr, only pets and mounts originally earned on the character being transferred go with that character, and it's NOT easy to get Blizz to transfer a character.
HOWEVER, if your husband does have UNLEARNED pets that are BoA, you MIGHT be able to "learn" them on a toon, then transfer that toon over to your account and the pets stay with. But I wouldn't count on this working, unfortunately.
Thaliana#1794 - My WoW account has 50 toons, so I would so greatly appreciate people creating toons on Kael'Thas or Ghostlands to trade with me. <3