Today is Raksha Bandhan or Rakhi which we celebrate as part of Nik's Indian culture and Hindu religion.
From Wikipedia: "Raksha Bandhan, also Rakshabandhan, is a popular, traditionally Hindu, annual rite, or ceremony, which is central to a festival of the same name, celebrated in India, some other parts of South Asia, and among people around the world influenced by Hindu culture."
Essentially it's a celebration of any brother-sister like relationship - "On this day, a sister ties a rakhi around the wrist of her brother in order to pray for his prosperity, health and well-being. The brother in return offers a gifts and promises to protect his sister from any harm and under every circumstance."
I made one using my old friendship bracelet making skills for Priya to give Kalyan. He wasn't fully on board but liked when it ticked and P wanted to keep the rakhi for herself but we did get it tied on, she was excited to show me that she can tie a knot herself.