Need Help Investing ₹1L Monthly – SIP, Stocks & Future Planning for My Family

Hey everyone, My father called me this morning and said we need to invest ₹1L per month for our future. Right now, we are starting with ₹1L, but we'll increase it later. We are a family of four (mom, dad, sister, and me). My initial plan is: ₹15K SIP for each of us (₹60K total). ₹40K in low-risk stocks (like Tata Motors, IREDA, etc.). The catch: My sister (24) will likely get married in 4-5 years, and I want to use the ₹40K/month investment to fund her grand wedding when the time comes. I am only 22, and my father is trusting me with this big responsibility. I don’t want to mess this up. What would be the smartest way to invest and grow this money while ensuring we have enough liquidity for my sister’s wedding? Any suggestions, strategies, or insights would be super helpful. Thanks in advance!