Awwww! How sweet. That reminds me of Fred when he brought home a pregnant stray. He would bring her morsels of food when it was uncomfortable for her to get up and bathe her when she was so huge.
He was my kitten loving boy. He would even kitten sit, and got the red-belly from an orphan that he would let nurse on for comfort.
Best wishes on an easy delivery and a happy little family.