Start a SIP so that you can create a corpus for your kids marriage. I would explain you through an example. If you have a one year old daughter, so start saving just Rs.10000 per month for the next 20 years. Which can give you around Rs.99 lakhs which includes 75 lakhs as profit and 24 lakhs as principal at growth rate of 12% CAGR.
This amount can be utilized for the wedding expenses. So the absolute returns comes to around 316.31% returns.
You can also invest in Retirement & pension planning by Investing in SIP