How would you reply your preschool Daughter if she ask" papa, mummy, why do boys stand up to pee and girls sit down to pee?" "What are those bumps on your chest, mummy?"

Tell the truth and use proper words :) Educate your daughter on body parts, safe and unsafe touches, what to do if someone tries to touch her in the "unsafe" areas etc. Most parents avoid the question, or try to give cutesy names to body parts - but neither of them help the kids at all. Comparing learning it from a parent and finding out about it themselves, I'd definitely share it with my child instead of trying to hide it.