Cheap/free stuff to do with a 2.5 year old Thursday and Friday

Need some low key stuff to get us out of the house Ideally nothing too active on my part, as I'm 38 weeks pregnant and my sciatica is really playing up. If it's fair weather can play in garden and bake and walk to local park and library but if it's not I absolutely hate staying in all day. Also, dad WFH so if he sees his dad, he wants him to play too