Devaki and Vasudeva prayed Lord and sought a boon for having Him as His son. He blessed them with it. Yashoda and Nandagopa prayed Lord and sought a boon that they raise Him. He blessed them with it. Sage Para:sara said… brunda:vanam bhagavatha: krushne:na aklishta karmana subhe:na manasa:dhya:tham gava:m vruddhim
Source: JIVA Shamshabad News