"My twin boys have always been rather fussy in the evenings. They are now 8 months old, and one of my boys does not seem to be outgrowing this tendency. We put them down at 7 and the hours between 4 and 6 (when bathtime begins) are punctuated by contant whining and fussing. It's driving me nuts. Bathtime goes well, and then he screams the whole time I dress hime until he gets fed. When he's not sleeping, he's extremely active. I'm pretty sure he's well-rested, as he takes 2 good naps per day (about 3.25 hours total) and sleeps 11 hours straight at night. Please give me some insight as to when this evening moodiness will end. I'm so tired of dreading that time of day."
Hmm. I know almost nothing about twins. If he was a singleton I'd look at either the nap schedule or something he's eating.
It may be possible that his second nap is just hitting him wrong, and he's waking up before he should be up (even 15 minutes can make a difference in this) or it's just hitting him at the wrong time of day somehow. I don't know if there's anything you can reasonably do about that, though, since I can't imagine dealing with two different nap schedules with twins. Maybe Linda or another twin mom can help us out with this one, because I'm a little daunted by the logistics of twin naps. (And I can't even bring myself, except in a parentehtical way, to suggest that maybe he needs a slightly earlier bedtime than your other son does.)
The other thing is that maybe there's something about something he's eating that isn't sitting right. Either he's got some kind of mild sensitivity or allergy, or maybe it's giving him heartburn or indigestion. Is there something he eats every day? If so, see if the fussiness stops if you don't feed him that for a week.
Oh, and is it possible that he's hungry during that time? Have you tried feeding him just a teeny snack right then?
(It just hit me that with twins there's always a control. Cool. I love the experimental method.)
I don't know if you live someplace that's cold right now, but the best thing I've ever done to get out from under the anvil of the 4-6 pm timeslot is go outside. In the warmer weather I'd just go walk around, and in the colder weather I'd go to the grocery store or another store (bearing in mind that I live in the city and can walk to the store, so this was all with the kid in the sling or stroller). The change of scenery seemed to provide enough diversion to break the fussy habit.
Get back to me and let me know if any of what I wrote was helpful.