On SB 9.21.25, Srila Prabhupada gives some interesting details about the life of Sukadeva Goswami.

Both Vyasadeva and Sukadeva are far from being ordinary persons. Vyasadeva is an incarnation of Krsna, who comes to restore Vedic knowledge when it’s almost lost at the end of Dvapara Yuga, while Sukadeva is considered to be an incarnation of the parrot of Srimati Radharani, who came especially to speak the Srimad Bhagavatam, illuminating thus the age of Kali. Being such an exalted soul, Sukadeva had a very profound understanding of spiritual relationships and was thus elected as the speaker of the Srimad Bhagavatam, even though both Vyasadeva and Narada Muni were present at the assembly.

The first interesting fact is that even a great personality like Vyasadeva didn’t get a pure son like Sukadeva Goswami automatically. Both he and his wife practiced austerities for many years before Sukadeva Goswami came as their son. There are other similar cases, like Vasudeva and Devaki practicing austerities as Sutapā and Pṛśni with the goal of obtaining Krsna as their son. Although great personalities like Vasudeva and Vyasadeva are already perfect, still they give us the example. Authorized austerities are a way to get a spiritually inclined son.

The second fact was that Sukadeva Goswami played the role of a Brahmavadi while inside the womb, showing fear of the material energy and thus refusing to come out. In total, he stayed inside the womb for 12 years, coming out only when Krsna Himself reassured him that he would not be captured by Maya. Even then, he immediately ran away from home, going immediately to the forest to live as a renunciant. With great difficulty, Vyasadeva was able to bring him back for a short period to listen to the Bhagavata Purana, which Sukadeva later expanded in the form of the Srimad Bhagavatam he spoke to Maharaja Pariksit.

The third fact is that Vyasadeva actually wrote the Srimad Bhagavatam two times, the first as the original Bhagavata Purana, which he compiled before the Mahabharata as one of the 18 Puranas, and later as the expanded Srimad Bhagavatam we have today, as explained by Srila Baladeva Vidyabhusana in his comment to the Tattva Sandarbha. I always thought Vyasadeva had waited until the Bhagavatam was spoken by Suta Goswami before finally writing it in palm leaves, but it seems more probable that he wrote the whole Srimad Bhagavatam, exactly in the way it would be later spoken by Suta Goswami to the sages of Naimisharanya immediately after his meeting with Narada Muni (narrated in the first canto). This is possible because Vyasadeva has vision of past, present, and future, and thus he could see events that would happen later.

Another interesting fact is that after hearing the Bhagavata Purana from Vyasadeva, Sukadeva Goswami expanded himself, with the original Sukadeva Goswami remaining as a lifelong brahmacari and the expansion returning home to stay with his father. This expansion of Sukadeva later entered family life and had a daughter.

Here is what Srila Prabhupada mentions in his purport on On SB 9.21.25:

“Śukadeva Gosvāmī, the son of Vyāsadeva, is described in great detail in the Brahma-vaivarta Purāṇa. There it is said that Vyāsadeva maintained the daughter of Jābāli as his wife and that after they performed penances together for many years, he placed his seed in her womb. The child remained in the womb of his mother for twelve years, and when the father asked the son to come out, the son replied that he would not come out unless he were completely liberated from the influence of māyā. Vyāsadeva then assured the child that he would not be influenced by māyā, but the child did not believe his father, for the father was still attached to his wife and children. Vyāsadeva then went to Dvārakā and informed the Personality of Godhead about his problem, and the Personality of Godhead, at Vyāsadeva’s request, went to Vyāsadeva’s cottage, where He assured the child in the womb that he would not be influenced by māyā. Thus assured, the child came out, but he immediately went away as a parivrājakācārya. When the father, very much aggrieved, began to follow his saintly boy, Śukadeva Gosvāmī, the boy created a duplicate Śukadeva, who later entered family life. Therefore, the śuka-kanyā, or daughter of Śukadeva, mentioned in this verse is the daughter of the duplicate or imitation Śukadeva. The original Śukadeva was a lifelong brahmacārī.”