Mine are also 3.5 years apart, and they do great. My ds6 is a very protective big brother - he hates if the neighbor boy (at the bus stop) picks on my dd2.5. Of course, she handles herself quite well. They argue but don't get excessively mean. When they have issues, we don't take sides (unless it's very apparent) and emphasize that they prolem solve. However, we won't tolerate cruelty on either's part. My ds has started reading books to my dd recently. I've got to sneak a video of this...it's so sweet.
