She met Augustus, Grand Duke of Oldenburg in 1830, and after an hour's conversation, the marriage was decided.

The hymn was later added with lyrics by Theodor von Kobbe and named ‘Heil dir, o Oldenburg’.

In honour of the late Cecilia, the locality Cäciliengroden at the Jade Bight near Wilhelmshaven (later incorporated into Sande in Frisia) was named after her.

Cecilia died at the age of 36 from puerperal fever, a few days after giving birth to her third child Elimar.

She was buried in the Ducal Mausoleum in the Churchyard of St. Gertrude (St. Gertrudenkirchhof / Gertrudenfriedhof) in the city of Oldenburg.