By nature, Golden Retrievers are extremely docile and gentle dogs regardless of sex, indeed, males sometimes tend to be calm compared to females. The difference in character is absolutely not between male and female, but each individual subject must be evaluated. Morphologically, males tend to be slightly larger than females, both in stature and weight. On a sexual level, a female who has reached maturity (around 9-12 months) will go into heat 2 times a year, while a male is always receptive if he senses a female in heat.