[DanBC]

In the pre-amble

"Recognizing that the child, for the full and harmonious development of his or her personality, should grow up in a family environment, in an atmosphere of happiness, love and understanding,"

And Article 3, section 1:

"1. In all actions concerning children, whether undertaken by public or private social welfare institutions, courts of law, administrative authorities or legislative bodies, the best interests of the child shall be a primary consideration."

[simoncion]

Article 3, section 1 has no bearing on the actions of the individual. Notice that the language that targets institutions and governments.

The preamble speaks only of the environment that a child should be placed in. If it is necessary that both parents work 120 hours per week to provide such an environment for their children, then that is behavior that is supported by that Convention.