I don't know I have a strong feeling that ahil is bill's step son. May be billi might have married ahil's father & he might have some psychiatric problem which he abuses ahil. Ahil's sisters will be bill's & ahil's father's kids. Ahil look much elder. If he was billi's son he should be 23yrs. I think billi killed ahil's Dad & manipulated in front of ahil.
Rehan said that he was adopted by billi. Why billi would adopt a kid unnecessarily? What if he is bill's real son? He has similarities of Imran. The way he speaks reminds me of Imran. Rehan does look like a 23 yr old guy.