SB 10.55.1
sri-suka uvaca
kamas tu vasudevamso
dagdhah prag rudra-manyuna
dehopapattaye bhuyas
tam eva pratyapadyata
Translation:
Sukadeva Gosvami said: Kamadeva [Cupid], an expansion of Vasudeva, had previously been burned to ashes by Rudra’s anger. Now, to obtain a new body, he merged back into the body of Lord Vasudeva.
Purport:
In his Krsna-sandarbha (Anuccheda 87), Srila Jiva Gosvami cites the following verse of the Gopala-tapani Upanisad (2.40) to prove that the Pradyumna who is the son of Krsna and Rukmini is the same Pradyumna who is a member of Lord Krsna’s eternal fourfold plenary expansion, the catur-vyuha:
yatrasau samsthitah krsnas
tribhih saktya samahitah
ramaniruddha-pradyumnai
rukminya sahito vibhuh
“There [in Dvaraka] the almighty Lord Krsna, endowed with His full potency, resided in the company of His three plenary expansions — Balarama, Aniruddha and Pradyumna.” The Krsna-sandarbha goes on to explain, with reference to the present verse of the Srimad-Bhagavatam, that “the Cupid whom Rudra burned up with his anger is a demigod subordinate to Indra. This demigod Cupid is a partial manifestation of the prototype Cupid, Pradyumna, who is a plenary expansion of Vasudeva. The demigod Cupid, being unable to attain a new body on his own, entered within the body of Pradyumna. Otherwise Cupid would have had to remain in a perpetual state of disembodiment, a result of Rudra’s having incinerated him with his anger.”
In his English rendering of the Srimad-Bhagavatam (1.14.30 purport), Srila Prabhupada confirms the absolute status of Pradyumna, Lord Krsna’s first son: “Pradyumna and Aniruddha are also expansions of the Personality of Godhead, and thus They are also visnu-tattva. At Dvaraka Lord Vasudeva is engaged in His transcendental pastimes along with His plenary expansions, namely Sankarsana, Pradyumna and Aniruddha, and therefore each and every one of Them can be addressed as the Personality of Godhead, …”
According to Srila Sridhara Svami, Pradyumna took birth from the womb of Rukmini before Sri Krsna’s marriage to Jambavati and the Lord’s other marriages took place. Subsequently, Pradyumna returned from Sambara’s palace. But before Sukadeva Gosvami tells of Krsna’s pastimes with His other wives, he will narrate the entire story of Pradyumna for the sake of continuity.
Srila Sridhara Svami further notes that Kamadeva, or Cupid, now appearing within Pradyumna, is a portion of Vasudeva because he is manifest from the element citta, consciousness, which is presided over by Vasudeva, and also because he (Cupid) is the cause of material generation. As the Lord states in the Bhagavad-gita (10.28), prajanas casmi kandarpah: “Of progenitors I am Kandarpa [Cupid].”