You should know about supplementary card

Supplementary cards: As the name suggests supplementary credit card is a card with an additional credit you can get on your existing credit card. When you ask the bank to issue a supplementary credit card on the basis of your own credit card (primary card), you can pass the supplementary credit to any family member like your parents, spouse, and children who are over the age of 18 years and the like. And, the number of supplementary credit cards which you can apply for varies from bank to bank, but it's usually in the range of three to five.

ReutersSupplementary cards can be used both in India and abroad to shop offline and online. Reuters
Benefits: Usually the benefits/ features of your supplementary cards are same as the benefits/ features you have on your primary credit card. Which means, a supplementary card can be used both in India and abroad to shop offline and online. The supplementary cards can also be used at an automated teller machines (ATMs) to withdraw cash as well. But, a few banks do offer supplementary cards with fewer benefits/ features as well. Supplementary swipes also gets the same reward points as your primary credit card.

How it works: Irrespective of the number of supplementary credit cards you take based on the primary credit card, to give to your family members, the bank will treat all the accounts as a single account. So, if your primary card limit is Rs 2 lakh, each supplementary card you apply for will have the same limit. So, in a way, if you have one supplementary card, the Rs 2 lakh gets divided between your primary card and the supplementary card you give to your family member. But the best part is that the primary card member has the option to not let the supplementary card have the same limit, instead allow a lower sub-limit on the supplementary card. So, if your primary card has a limit of Rs 2 lakh, you can set the supplementary card limit to say Rs 25,000. Sub-limits can be set even on ATM cash withdrawals.
In fact, you will get a single account statement being the primary card holder and hence you get to know the details of the supplementary card holder's transactions. This works well, especially if you want to give your supplementary card to adult children's, who are still students. Supplementary cards let parents monitor the spends on adult child's cards.

Cost: The cost you will have to bear for supplementary cards will vary from bank to bank. Some banks may offer up to three supplementary cards free. Others may charge a few hundred rupees while others may ask you to pay a joining fee as well.

Most important thing: The most important things to know about supplementary cards is that since you are the primary holder of the card, it's your responsibility to take care of the dues, since it's a single account. Also, know that the supplementary cards are also mentioned on your individual credit report.
Supplementary cards work very well when you want to give your aged parents or adult children who are financially dependent on you (like students). The best part is you can track their spend and also set the sub-limits as a primary card holder.