You treat the first like they might break, all gentle gentle.

Then you have a toddler and a baby.

She is 2.5 years older than he is. She sits on him. She pushes him off the couch. She steals toys off him. She feeds him mud. She feeds him peanuts. She barricades him into the hallway. She buries him with blankets and toys. She fills his pockets (or his nappy) with gravel, twigs or mashed food. She slams doors in his face. She opens other doors for him so he can crawl off down the street.

He's still a happy little thing with surprisingly few injuries ...