Gift from father's sister.

Gift income can be included in any return form, under Income from Other Sources, there will be a head mentioning Gift where you can mention the amount. Since father's sister is a relative as per the act, the amount will be non taxable.

Depending upon what other sources of income your son has, relevant ITR form will have to be filled. Most probably since he doesn't have a business/profession and is just earning gift income and maybe some bank interest ITR 2 will have to be filed.

agree with Arun sir ....