My two flop back and forth between Mom and Dad’s house every week on Sunday afternoons. They are 6 year old twins, and this has been going on for about 3 years now. They have complete bedrooms, wardrobes, sets of toys, dogs, etc. at BOTH houses, so there is no packing involved. From what I’ve read this was considered a bit of a radical approach a few years back, but is now apparently common enough not to raise eyebrows.
Wednesday night is Boys and Girls night. We started this mainly to combat a twins-with-single-parents problem, but it might (or might not) be something to think about in any two-child household. Every Wednesday, we each get ONE of the kids after school, and keep them until we drop them off at school the next morning. This gives the child one night a week to have a Parent’s undivided attention, and to get to choose their own activities, games, books, food, etc. etc. without always having to take their twin into consideration. It also gives the Parent a chance to, well, PARENT, without always being outnumbered two to one. The original idea was for me to always get the boy and Mom to always get the girl and allow for a little same-sex bonding, but the kids vetoed this a few weeks in. They both wanted solo time with both parents. So now we leave it up to them. Whoever has them just asks on Tuesday night who is going with whom tomorrow, and they tell us. Neither parent has ever heard them negotiating this, so they must do it at school, because they always both know the answer at once.
So far the whole system has worked pretty well, though we expect things will have to change as they get older.
Good luck.