[1] Trehan joined the Arya Samaj as a teenager when while attending an opening meeting the attendees were surrounded by police and beaten up.
[3] That time she was working along [[Bibi Raghbir Kaur]] who was a Kirti-Ghadar Party member of Punjab State Legislative assembly.
[2] Trehan traveled the remote villages of Punjab to encourage women to cook, sew and clean.
[1] After India's independence, Trehan continued to promote education for children and opened three girls' schools and one co-education.
Until her death in 2011, she tackled the social problems at the grassroots level – dowry, domestic violence, casteism and inter-caste marriage.