4 adults, 2 toddlers, well, at least the adults do have them out numbered.  There is not a lot of detail in this question.  Do the children have a set routine?  It is important that children, especially toddlers have the same routine daily, time set to eat and time set for bed.  I believe that children that stick to a set routine naturally behave better, when it's bedtime, they are ready to go to bed.  A nightly ritual is helpful, bath, brush teeth, use potty, read story and night-night.  They should be calm and ready to sleep and not wanting to ambush the room if left alone.  Do the children stay at day care or with a sitter or with the Mother?  Children that stay with their Mother perform better and stay on a routine more likely than children that are left with the sitter, sitters tend to let the children take lengthy naps, which cause the children to be up later at night, diets?  Too much sugar intake also stirs up the rowdiness.  Do keep in mind that 28 months is in the "terrible two era" that will soon pass.  Time outs should be used carefully, 1 minute per age of child 2 years old = 2 minute time out and you may want to try separating the children at bed time (strength in numbers).  Good luck!