Duke Xuan's original heir apparent was Crown Prince Yukou, but after Duke Mu was born, he killed Yukou and made Kuan his new heir apparent.
[1][2] Yukou was close to Chen Wan (陳完), the son of Duke Li.
[1] In 653 BC, Prince Kuan represented Chen at a conference at Ningmu in the State of Lu, and made an alliance with Duke Huan of Qi, Duke Xi of Lu, Duke Huan of Song, and Crown Prince Hua of Zheng.
Kuan succeeded his father as ruler of Chen, to be known as Duke Mu.
[1] Duke Mu reigned for 16 years and died in 632 BC.