[3] Her father founded a health service company, where he was also the chief executive, and her mother is an international tax consultant and partner at a national public accounting and business advisory firm.

[7] In 2016, she was chosen by choreographer Christopher Wheeldon to create a lead role in American Rhapsody,[8] and by Lauren Lovette in For Clara.

[4] Since then, she has danced featured roles, including in "Emerald" from Jewels,[12] A Midsummer Night's Dream,[13] Liebeslieder Walzer,[14] Orpheus,[15] Divertimento No.

15;[16] Robbins' Dances at a Gathering,[17] In G Major[18] and Antique Epigraphs;[19] Wheeldon's Polyphonia[20] and DGV: Danse à Grande Vitesse;[21] and Forsythe's Herman Schmermen.

[28] Phelan appeared in the 2019 film, John Wick: Chapter 3 – Parabellum, as a ballerina who is also training to be an assassin, with the dance sequences choreographed by Tiler Peck.

[29] She then appeared in a dream ballet sequence in the 2020 film, I'm Thinking of Ending Things, choreographed by Peter Walker.

[33] Ballets she performed since her promotion include Balanchine's Agon, Tschaikovsky Pas de Deux,[a] Apollo (as Terpsichore), Symphony in C, Stravinsky Violin Concerto, Vienna Waltzes, La Sonnambula (as the Sleepwalker), A Midsummer Night's Dream (as Titania), Swan Lake, and Robbins' Piano Pieces.