how do i help my partner?

my partner is trans and she has had experiences in the past where little kids would be talking about her asking "what gender are they?" within earshot and it has hurt her self-esteem a ton. i genuinely don't know how or why anyone would be asking this as she passes 100%. i have been here to reassure her that she passes and she is the most beautiful girl in the world but it's hard to break through when experiences like that happen. does anyone have any advice to help her? i really want her to be able to live life and be able to go outside

i just want to be more knowledgeable to help in anyway i can, i know i can never truly understand what she goes through but any bit could help, thanks all