Stacking toys dexterity

Around what age do babies start shape sorting, stacking blocks, and rings? My MIL laughs about my son not being able to do it. He is 10 months in a week. I do this with him every day and the most he will do is knock a tower down and pull blocks and rings off once I stack them. I am not over concerned as he seems quite interested in how things work now plus not all kids grow up with these toys. She used to be a teacher and won't offer any help so just wondering if I am delaying his development.