Is it safe for babies to have x-rays?

Simple answer, if the pros outway the cons then yes.

Properly conducted imaging carries minimal risks and should be performed when clinically indicated.

A valuable summary is available at: http://www.radiologyinfo.org/en/pdf/sfty_xray.pdf

X-rays must not done repeatedly, once may not be harmful specially if it is necessary to diagnose a certain disease.

Yes, it is safe for babies to have xrays.

It is better to avoid x-ray at any age but the value of x-ray may be very high in management of the disease. Good doctors weigh risk of x-ray with benefit and then decide what they think is appropriate

 X-rays and scans can be helpful, even life-saving. But sometimes, they're not necessary.

So when are these tests really needed 

I can't say it is safe but if clinically indicated it must be performed.

it's not safe, because it's an agression for the incopmlited bones 

yes of cours  . no conter indication 

IF THERE IS CLINICAL AND MEDICAL INDICATION

X rays should done when indicated as repeated x ray may carry risk of radiation and it is sequalae