BuddyPress.org

If you’re using Thesis as the parent theme, you’ll have to enable BP support for your theme.

Two options:

1) Use the BP Template Pack plugin:

https://wordpress.org/extend/plugins/bp-template-pack/

2) Manually add BP support to your theme.

thekmen has added BP support to a child theme of the Hybrid framework:

https://buddypress.org/forums/topic/testing-new-theme-hybrid-as-a-parent#post-40217

You can check out what he did as a guide.