After doing a hive inspection yesterday, it appears that one of my hives is either queenless or has a defunct queen. This must have been going on for quite some time, because I have noticed that this hive has been rather weak for about 1.5 months. There is very little brood in the hive, and there aren't a lot of bees either. This is my first year, so I don't know exactly what I should do. Should I requeen, or should I combine this hive with a stronger one? I could take a tray or two of brood from one of my three other hives and add it to this weak one, but there may not be enough bees to take care of much brood.