Sisters..Where art thou?

My little boy used to have a few imaginary friends. I wasn't quite sure what their names were but he always seemed to have fun with them. Ever since he developed his kidney ailment, he's been confined at home most of the time to prevent risk of infections. His medication does cut down his own natural immune system therefore a simple cold may lead to a trip to ER. He does play well on his own when he is at home but he seems to light up when he is around kids his age or slightly older. He longs to visit his friends and always asks us to bring him to their home to play or visit. Every time, when a friend comes over to play with him, the moment of his friend returning home is like the ending scene of Romeo and Juliet where tears rain down like a fierce thunderstorm.
Lately we have been feeding him on the idea of perhaps being a brother. He didn't like it at first but he is starting to warm up to the idea. We even picked out his sisters names, and for now, he would just have to imagine that they are there with him. Today, all of a sudden, he said something so sweet that almost melt our hearts. He told us that he would read his sisters bed time stories and would even share his toys, food and his most important precious the OG's with them.