[Shugart23]

This might already have been asked and answered. I’m telling my son that doubles and cue bids don’t need to be alerted since they implicitly should alert the opponent. True or false with a counter example?

[blackshoe]

False IMO, in the ACBL. Other jurisdictions may have different rules. ACBL's rules are here.

[pescetom]

False in Italy, a fairly typical and modestly orthodox WBF feud.
Doubles are automatically alerted only if they show or deny length in one or more known suits, and even that mysteriously disappears (no such words in regulations) if one promises 4 in the other major or 4-3 or 4-4 in majors. Nevertheless, one is encouraged to alert agreements that are unusual and for instance I always alert support double which is rare over here.
Cue bids (better known as overcalls here, where overcalls are known as intervention and cue bids are (only) control-bids) are always alertable if they do not show the same suit naturally. Control-bids below 3NT or in the first round of bidding are alertable for the same reason.

[smerriman]

Seems familiar.