Posted for a reader.
You are a baal/at teshuvah (returnee to Judaism), and the rest of your immediate family are secular. You are the only religious Jew they know, and they see you as different and a little strange. Your little niece loves to spend time with you and your family at your house. She is 10.
How do you teach her about modesty and how to dress when she comes to visit you? How do you explain to her to bring clothing that covers her up at all times, without hurting her feelings? That it isn’t appropriate for her to be running around the house in short shorts and tank tops, especially when you are trying to raise your children to dress modestly?
Speaking to her parents apparently does no good as they have not been around religious people much and really think this whole religious idea about dressing modest is cultish and strange.
Your niece loves to visit, she enjoys the vibe in your home, and loves the ritual of Judaism that she sees. It is quite possible that due to her visits a spark could be ignited within her and she could follow your path towards observance.
Is this worth addressing, or will the child, as she grows older, learn that at her aunt and uncle’s house we dress differently, and she will do that in her own time?