Rodolfo
That is close to my current demographic and the vast majority of the pilots here who I know well are the same (i.e wife not working or very low paid part time) and two children under 19. A smattering of them have 3 children but the vast majority have two mostly in junior (that is under 12yrs old for UK system)
As an FO (WITH NO DEBT) you get paid enough to live a reasonable life in a nice house and break even.
It is possible to save something but very very little i.e $500 per month would be good. To save more you have to sacrifice something. So reduce your accommodation costs by living in a less desirable area, stay in more, choose not to have a maid, choose not to have pets, don't do Extra Curricula Activities for the children, no holidays, and get rid of anything that is a cost in your home country
. (i.e if you have a house it must be rented or sold at home not empty for when you need it)
As a CAPT again (WITH NO DEBT) then you are 15,000AED per month better off so basically you wait 2-3 yrs get your command and then you can do the things you sacrificed before.
Suddenly family holidays, that nicer car and a new bike for the kids is not hmmm maybe next year. It is something you can do at the time. That investment property back home can be added to/bought/traded up etc.
Basically your life is fine as an FO but do not expect to save anything if you want to have a reasonable life but you can offset that as a skipper. If you have stuff that needs paying off at home then factor that in and it is fairly likely that you will end up with 5,10 or even 15,000AED per month deficit unless you reduce something. Some/most things cannot be reduced substantially so your options are take a loan pay it all off and likely reduce your sources of irritation OR live on credit until you get upgraded. (I think one of these to be more sensible than the other) but it is all personal choice.
Suffice to say yes you can live as a family of 4 on an FOs salary but not indefinitely!
Have a good weekend
VT