Sedney won two gold medals at the 2017 European Youth Summer Olympic Festival.

In 2022, she became part of the 4 × 100 metres Dutch relay team, competing together with her older sister Naomi Sedney.

[11] In 2021, Sedney competed in her first international senior competition at the European Indoor Championships in Toruń, Poland.

[15] In March, Sedney represented the Netherlands in the World Indoor Championships in Belgrade, Serbia.

In Eugene, Sedney finished 6th in her heat of the 60 metres hurdles in 13.38 s. This was not enough to progress to the semi finals.

Sedney stated she had less joy in hurdles and decided with her coaches (Laurent Meuwly and Brendan Troost)[citation needed] to make the switch.

She was in the stands cheering on the Dutch team (Eveline Saalberg, Lieke Klaver, Cathelijn Peeters, and Femke Bol) as they won the gold.