Validity of Child Visa

by Manoj
(Jebel Ali,Dubai,UAE)

Dear Sir,
My daughter is studying in Grade 3 in India and has a UAE valid residence visa.Since she is studying there at the moment, is it mandatory to have her enter UAE within every 6 months or can an extension be possible .Can she enter the country after say 10 months after finishing the academic year.
If so what is the procedure involved

Pl. advise

rgds
Manoj