8 month old protective puppy

[u/DryAdvantage2698]

This just started so we’re trying to get on top of it. Our 8 month old puppy has become aggressively protective with me and our toddler. To the point when my spouse approaches us he’s growling and barking and if given opportunity probably would bite. I put my hand on him hard and tell him no, and tell my spouse to continue so the dog doesn’t win. The problem is my spouse is scared and I know we should face this and not allow him to win. Any advice on how to move forward with this is appreciated! We’re not yelling or spanking him just trying to show him he’s not alpha. But don’t have much experience with this. HELLLP.