Que tenga un día de fiesta seguro y magnífico.
Yes it is correct to say "Have a wonderful Holiday."
"Esto magnifico" (the 'I' is implied)
niños maravillosos
You can say holiday as fiesta, which also means party.
día festivo
Holiday: Festivo, feriado
You can use the expression, "Bonne vacances!" in French, which literally means, "Good holiday," but would translate out to, "Have a good holiday!"
sin vacaciones
me- dee- ahh- de- fiesta
Ir de vacaciones
La vida es maravillosa
Los videos son maravillosos.