I would love to have the ability to query a list of birthday on a descendant of someone, for example my grandfather's descendants from my mother's side.
Currently the existing "Calendar" section will show quiet a lot of profiles which will also include a non-direct family to this list. It is a bit trouble for me to open each profile to know if they are directly related when the query returns hundreds of them only for a month.
Basically this request is for user to have more flexibility to query what we only want. Timeline is a good example, but still lack of several options.