Hi and welcome to the site. I, too, am a sewing grandma. I have all grandsons and have made the pajamas, short, sunsuits, sweatshirts, sweatpants, etc. Two of my grandsons like the boxer shorts and they are very easy to make. Also now that the flannel pants are in for relaxing in they love those. I have made MANY fleece jackets for "my boys", even for my adult boys. Fleece is so easy to work on. If I had a daughter or GD I would have a ball making things for her! I have also done a lot of sewing for myself over the years. Don't do as much of that now so I'm hoping I can do more quilting.
Judyjo