Definites: I'm sure Bee's mom could put the kids down if needed, as she's done it in the past. Also, our kids' old daycare director put them down for their naps for years, and she had no problems doing bedtime too! (She babysat for us a while ago.)
Probables: I'm guessing that two friends of ours could put the kids down too, but we have yet to test that one! They have two kids too so putting four kids down at night might be a bit daunting. But with two parents, they could probably pull it off.