You can apply if you are married, but the contract is 'single'- i.e. benefits such as housing and visa sponsorship are for yourself only.
There are ladies who have joined who are married with kids and husband in home country, who have moved later on. However the husband would need to find his own job to get a visa - as far as I can find out a cc (especially on starting wage) would not qualify to sponsor her husband. So the best situation would be if he already had got a job and package in Dubai with housing etc... then you could join him later on. Of course, all is dependent on you BOTH getting a job here.
Schooling can be an issue as well, it can be expensive and at the moment CC do not get education allowance for kids. It is possible, as others have done it, but it would not be easy.
There is also the possibility of 'live out allowance'- i.e. you join as single, apply for the allowance where you are given an amount toward rent and you get your own place. Howver, this is not guaranteed and is on case by case basis. Priority is given to senior crew. I would personally not rely on this part as a given plan.
Good luck
Edit: This is for EK, I think EY is similar but not sure about QR sorry