Attending weddings must be a frequent activity if you get invited when anyone within 3 or more degrees of separation is getting married. Really, how often does an average Indian attend weddings? Are expensive gifts expected?
For distant relatives no gift is expected, but people do give cash(1000rs avg). For close relatives it's mostly gold. You are supposed to return equal or more than you received for your sons/daughters marriage. It can average 8gms of 22k gold (cost upto 30000rs) which is not a small amount.
Also all of these varies between states, religions and caste. For e.g no one expects dowry in West Bengal while in neighbouring state you are expected to give hefty dowries.