Because Nabhaga did not return from the place of his spiritual master, his brothers thought that he had taken brhadvrata-brahmacarya. Therefore, they did not preserve his share, and when he returned they gave him their father as his share

Expressions researched:
"Because Nābhāga did not return from the place of his spiritual master, his brothers thought that he had taken bṛhadvrata-brahmacarya. Therefore, they did not preserve his share, and when he returned they gave him their father as his share"

Srimad-Bhagavatam

SB Canto 9

The bṛhad-vrata brahmacārī does not return from the place of the spiritual master; he stays there, and later he directly takes sannyāsa. Because Nābhāga did not return from the place of his spiritual master, his brothers thought that he had taken bṛhadvrata-brahmacarya. Therefore, they did not preserve his share, and when he returned they gave him their father as his share.

SB 9.4.1, Translation and Purport

Śukadeva Gosvāmī said: The son of Nabhaga named Nābhāga lived for a long time at the place of his spiritual master. Therefore, his brothers thought that he was not going to become a gṛhastha and would not return. Consequently, without providing a share for him, they divided the property of their father among themselves. When Nābhāga returned from the place of his spiritual master, they gave him their father as his share.

There are two kinds of brahmacārīs. One may return home, marry and become a householder, whereas the other, known as bṛhad-vrata, takes a vow to remain a brahmacārī perpetually. The bṛhad-vrata brahmacārī does not return from the place of the spiritual master; he stays there, and later he directly takes sannyāsa. Because Nābhāga did not return from the place of his spiritual master, his brothers thought that he had taken bṛhadvrata-brahmacarya. Therefore, they did not preserve his share, and when he returned they gave him their father as his share.