Tell

[Jellybaby]

¿Cómo se dice...?

"Tell daddy to go and get the girl so she can get our ball back."
(In a bar with a zona de juegos and the kids had kicked the ball over the wall, so needed the waitress to get it back for us.)

"Diselo a daddy que vaya a encontrar la chica para que nos pueda delvolver la pelota."

[poli]

Dile a papá que vaya a recoger la bola que la chica que que trabar el el bar tiene guardada.

[Julvenzor]

Tal como lo entiendo:

Dile a papá que vaya a recoger la pelota que la camarera tiene guardada.

Dile a papá que vaya al bar para que la camarera nos devuelva la pelota.

Un saludo a ambos.

[poli]

Por algún problema del interne, no pude corregir mi hilo. Habían errors.
Gracias Julvenzor.

[Jellybaby]

Thanks to both of you but neither translate exactly what I mean.
The girl didn't have the ball the kids had kicked the ball behind the wall where the kids play area was and the girl who worked there was the only one to be able to get it as the part where it was, was restricted to customers.

[poli]

Dile a papá que hable con la señorita que trabaja en la taverna. Ella trabaja en el edificio donde cayó la bola (pelota).

[AngelicaDeAlquezar]

Your sentence is fine with these suggestions:

"Diselo (Only indirect object. If you use "lo" is because your listener already knows what you are going to say.) a daddy (If you talk like this to your children, that's alright, but since you're asking for a translation in Spanish, you need to use the equivalent word) que vaya a encontrar *** ("Personal a (http://grammar.tomisimo.org/Personal_a)" missing) la chica para que nos pueda delvolver (Check spelling) la pelota."