@Anonemouse1 thank you for replying. So, from the beginning was told us by the clinic that they will secure that the child from egg donation would it be possible to be from our genetics. So, for the ones who see it from outside, they will never know. The doctor who told us that is now not working anymore there and during my pregnancy the other doctors changed a bit this message about possibilities.
What we said from the beginning to people is that we did treatments but we didnt talk about this specific part of it. Also, when they ask we receive different kind of comments : 'oh he is so different from the brother!', 'its so white like not indian', 'he is almost blond', 'he is very big when comparing with brother at same age', 'this boy needs to be swapped at the hospital'. Friends and also family saying this kind of things like surprised or joking.
We usually answer saying 'yes. So different from the brother, but also my husband' s granmother was a bit lighter than us' or 'yes, see how they are different', or 'our oldest son also changed so much from baby to now'. But its difficult because I go home crying.
The thing is that we dont know how it will be in the future after some summer living. But we believe people can compare a lot or even distinguish between them, specially my family. So, we believe we are protecting them doing this.