Males and females are different as friends and typical as husband & wife, this is universal phenomena. I’m surprised that he wants you to be strict with your daughter; most commonly husband keeps on advising wife to go softer with kids. It is a mother who is practically stricter with child, father’s strictness theoretical. Exceptions are always there as statistical rule. I’m not sure on what issues he wants you to be strict so difficult to suggest specific points. You can tell her about your past life when she grows beyond 10. Exact age depends upon her maturity level, emotional growth, her personality, her surroundings etc.