Hi Dipen -- certainly working in your family business "counts" towards your work experience. The issue is "how much" does it count.
If you were studying full-time in your masters *and* claiming to work full-time, then this will raise questions; some people have managed to do both "full time" but that would be unusual and invite some degree of skepticism.
However the real answer depends on questions like: what was the substance of your work? What role were you in? What impact did you have? What skills/knowledge did you acquire? These factors are considered by the AdComs whether you're working in a family business or not.
Personally, I'd be a little conservative and not claim "2 years" of FT work experience while you were doing your masters. I'd discount that by (say) 25-50% and claim between 12 months and 18 months of additional experience IF you were really working close to full-time. If you were working less, then discount further.
However, it's not all bad news! In fact, we've seen situations where people working in a family business have had more advanced experiences and responsibilities than they would have received working in a "normal" job. So this *can* be a competitive factor in your favor.
However another challenge about your family business experience relates to securing references from your family business. The AdCom is simply not going to accept that your family members are unbaised; you must secure references from outside the family.
So in summary, look deeply into the substance of your achievements, what you've learned, what you're bringing to the table for your future classmates from these experiences; these questions matter.
Hope that helps. Best wishes for success with your MBA campaign and your future career!
Cheers, Chris