Within a Rs 15 lakh budget, your best option is the Kia Carens Clavis HTE (O), which comes with two engine options. As a family car, the 1.5 NA engine does the job. It is smooth and quite responsive in slow traffic. If you want a bit more power, the 1.5 turbo-petrol is a good option, particularly for highway runs and long weekend trips.
The Kia Carens Clavis has a well-designed cabin with a spacious and comfortable third row, which is good even for adults.