Sieglien obtained a degree Master of law at the KULeuven in 2014. In 2015 she obtained a specialised master in social law at the Université Libre de Bruxelles. She also happens to have a flair for languages. Sieglien can express herself fluently in Dutch, French, English and Romanian. Last but not least she also has a basic notion of Russian and German.

Sieglien joined the team of Claeys & Engels in September 2015 and is now a member of the Bar in Kortrijk.