What is 'Have a sweet dream' in French?

Fais de beaux rêves is a French equivalent of 'Have a sweet dream'. The imperative 'fais' means '[informal you] do, make'. The partitive 'de' means 'some'. The masculine plural adjective 'beaux' means 'beautiful, handsome'. The masculine plural noun 'rêves' means 'dreams'. All together, they're pronounced 'feh duh boh rehv'.

That's what's said to someone within the speaker's close circle of family, friends and peers. It's something else to more than one person, or to a person or persons senior in age or position or outside that close familial and friendly circle. In the two preceding cases, it's 'Faites de beaux rêves'. It's pronounced 'feht duh boh rehv'.