Two possible avenues to a right of residence, one long shot and one quite possible.
The quite possible route is if her father was ever a worker in the UK while she was installed here. If so, she has a derivative right to reside for as long as she remains in education, including higher education if it comes to that (leaving aside the eligibility of students for HB generally). Her mother’s derivative right to reside falls away when she no longer needs parental support to remain in education, but her own derivative right to reside continues for as long as she is a student. Some of the very early Baumbast/Teixeira type cases were about young adults seeking equal access to student finance.
The long shot is that her mother at some point in the past acquired a permanent right to reside, perhaps through five years of marriage to her father while he had a right to reside in some capacity other than as a worker, or as a worker before the claimant was installed in the UK; and that the mother now has settled or pre-settled status. In that case, she would have a right to reside as a descendant aged under 21 of her mother who in turn has a right to reside herself
